text: // Copyright (c) 2012 The Chromium Authors. All rights reserved.
  // Use of this source code is governed by a BSD-style license that can be
  // found in the LICENSE file.
  
  #include "chrome/browser/chrome_content_browser_client.h"
  
  #include <set>
  #include <utility>
  #include <vector>
  
  #include "base/bind.h"
  #include "base/command_line.h"
  #include "base/files/scoped_file.h"
  #include "base/i18n/icu_util.h"
  #include "base/lazy_instance.h"
  #include "base/path_service.h"
  #include "base/prefs/pref_service.h"
  #include "base/prefs/scoped_user_pref_update.h"
  #include "base/strings/string_number_conversions.h"
  #include "base/strings/utf_string_conversions.h"
  #include "base/threading/sequenced_worker_pool.h"
  #include "chrome/browser/browser_about_handler.h"
  #include "chrome/browser/browser_process.h"
  #include "chrome/browser/browser_shutdown.h"
  #include "chrome/browser/browsing_data/browsing_data_helper.h"
  #include "chrome/browser/browsing_data/browsing_data_remover.h"
  #include "chrome/browser/character_encoding.h"
  #include "chrome/browser/chrome_content_browser_client_parts.h"
  #include "chrome/browser/chrome_net_benchmarking_message_filter.h"
  #include "chrome/browser/chrome_quota_permission_context.h"
  #include "chrome/browser/content_settings/cookie_settings.h"
  #include "chrome/browser/content_settings/tab_specific_content_settings.h"
  #include "chrome/browser/defaults.h"
  #include "chrome/browser/download/download_prefs.h"
  #include "chrome/browser/font_family_cache.h"
  #include "chrome/browser/geolocation/chrome_access_token_store.h"
  #include "chrome/browser/geolocation/geolocation_permission_context.h"
  #include "chrome/browser/geolocation/geolocation_permission_context_factory.h"
  #include "chrome/browser/media/cast_transport_host_filter.h"
  #include "chrome/browser/media/media_capture_devices_dispatcher.h"
  #include "chrome/browser/media/midi_permission_context.h"
  #include "chrome/browser/media/midi_permission_context_factory.h"
  #include "chrome/browser/metrics/chrome_browser_main_extra_parts_metrics.h"
  #include "chrome/browser/nacl_host/nacl_browser_delegate_impl.h"
  #include "chrome/browser/net/chrome_net_log.h"
  #include "chrome/browser/notifications/desktop_notification_service.h"
  #include "chrome/browser/notifications/desktop_notification_service_factory.h"
  #include "chrome/browser/notifications/platform_notification_service_impl.h"
  #include "chrome/browser/platform_util.h"
  #include "chrome/browser/prerender/prerender_final_status.h"
  #include "chrome/browser/prerender/prerender_manager.h"
  #include "chrome/browser/prerender/prerender_manager_factory.h"
  #include "chrome/browser/prerender/prerender_message_filter.h"
  #include "chrome/browser/prerender/prerender_tracker.h"
  #include "chrome/browser/printing/printing_message_filter.h"
  #include "chrome/browser/profiles/chrome_browser_main_extra_parts_profiles.h"
  #include "chrome/browser/profiles/profile.h"
  #include "chrome/browser/profiles/profile_io_data.h"
  #include "chrome/browser/renderer_host/chrome_render_message_filter.h"
  #include "chrome/browser/renderer_host/pepper/chrome_browser_pepper_host_factory.h"
  #include "chrome/browser/search/instant_service.h"
  #include "chrome/browser/search/instant_service_factory.h"
  #include "chrome/browser/search/search.h"
  #include "chrome/browser/search_engines/search_provider_install_state_message_filter.h"
  #include "chrome/browser/services/gcm/push_messaging_permission_context.h"
  #include "chrome/browser/services/gcm/push_messaging_permission_context_factory.h"
  #include "chrome/browser/signin/principals_message_filter.h"
  #include "chrome/browser/speech/chrome_speech_recognition_manager_delegate.h"
  #include "chrome/browser/speech/tts_controller.h"
  #include "chrome/browser/speech/tts_message_filter.h"
  #include "chrome/browser/ssl/ssl_add_certificate.h"
  #include "chrome/browser/ssl/ssl_blocking_page.h"
  #include "chrome/browser/ssl/ssl_client_certificate_selector.h"
  #include "chrome/browser/ssl/ssl_error_handler.h"
  #include "chrome/browser/sync_file_system/local/sync_file_system_backend.h"
  #include "chrome/browser/tab_contents/tab_util.h"
  #include "chrome/browser/ui/blocked_content/blocked_window_params.h"
  #include "chrome/browser/ui/blocked_content/popup_blocker_tab_helper.h"
  #include "chrome/browser/ui/chrome_select_file_policy.h"
  #include "chrome/browser/ui/sync/sync_promo_ui.h"
  #include "chrome/browser/ui/tab_contents/chrome_web_contents_view_delegate.h"
  #include "chrome/browser/ui/webui/chrome_web_ui_controller_factory.h"
  #include "chrome/common/chrome_constants.h"
  #include "chrome/common/chrome_paths.h"
  #include "chrome/common/chrome_switches.h"
  #include "chrome/common/env_vars.h"
  #include "chrome/common/logging_chrome.h"
  #include "chrome/common/pepper_permission_util.h"
  #include "chrome/common/pref_names.h"
  #include "chrome/common/render_messages.h"
  #include "chrome/common/url_constants.h"
  #include "chrome/grit/generated_resources.h"
  #include "chrome/installer/util/google_update_settings.h"
  #include "chromeos/chromeos_constants.h"
  #include "components/cdm/browser/cdm_message_filter_android.h"
  #include "components/cloud_devices/common/cloud_devices_switches.h"
  #include "components/content_settings/core/browser/content_settings_provider.h"
  #include "components/content_settings/core/browser/content_settings_utils.h"
  #include "components/content_settings/core/browser/host_content_settings_map.h"
  #include "components/content_settings/core/common/content_settings.h"
  #include "components/content_settings/core/common/permission_request_id.h"
  #include "components/dom_distiller/core/url_constants.h"
  #include "components/google/core/browser/google_util.h"
  #include "components/metrics/client_info.h"
  #include "components/pref_registry/pref_registry_syncable.h"
  #include "components/signin/core/common/profile_management_switches.h"
  #include "components/translate/core/common/translate_switches.h"
  #include "content/public/browser/browser_child_process_host.h"
  #include "content/public/browser/browser_main_parts.h"
  #include "content/public/browser/browser_ppapi_host.h"
  #include "content/public/browser/browser_thread.h"
  #include "content/public/browser/browser_url_handler.h"
  #include "content/public/browser/child_process_data.h"
  #include "content/public/browser/child_process_security_policy.h"
  #include "content/public/browser/permission_type.h"
  #include "content/public/browser/render_frame_host.h"
  #include "content/public/browser/render_process_host.h"
  #include "content/public/browser/render_view_host.h"
  #include "content/public/browser/resource_context.h"
  #include "content/public/browser/site_instance.h"
  #include "content/public/browser/web_contents.h"
  #include "content/public/common/child_process_host.h"
  #include "content/public/common/content_descriptors.h"
  #include "content/public/common/url_utils.h"
  #include "content/public/common/web_preferences.h"
  #include "gin/public/isolate_holder.h"
  #include "net/base/mime_util.h"
  #include "net/cookies/canonical_cookie.h"
  #include "net/cookies/cookie_options.h"
  #include "net/ssl/ssl_cert_request_info.h"
  #include "ppapi/host/ppapi_host.h"
  #include "storage/browser/fileapi/external_mount_points.h"
  #include "ui/base/l10n/l10n_util.h"
  #include "ui/base/resource/resource_bundle.h"
  #include "ui/resources/grit/ui_resources.h"
  
  #if defined(OS_WIN)
  #include "base/win/windows_version.h"
  #include "chrome/browser/chrome_browser_main_win.h"
  #include "sandbox/win/src/sandbox_policy.h"
  #elif defined(OS_MACOSX)
  #include "chrome/browser/chrome_browser_main_mac.h"
  #include "chrome/browser/spellchecker/spellcheck_message_filter_mac.h"
  #include "components/crash/app/breakpad_mac.h"
  #elif defined(OS_CHROMEOS)
  #include "chrome/browser/chromeos/chrome_browser_main_chromeos.h"
  #include "chrome/browser/chromeos/drive/fileapi/file_system_backend_delegate.h"
  #include "chrome/browser/chromeos/file_manager/app_id.h"
  #include "chrome/browser/chromeos/file_system_provider/fileapi/backend_delegate.h"
  #include "chrome/browser/chromeos/fileapi/file_system_backend.h"
  #include "chrome/browser/chromeos/fileapi/mtp_file_system_backend_delegate.h"
  #include "chrome/browser/chromeos/login/startup_utils.h"
  #include "chrome/browser/chromeos/system/input_device_settings.h"
  #include "chromeos/chromeos_switches.h"
  #include "components/user_manager/user_manager.h"
  #elif defined(OS_LINUX)
  #include "chrome/browser/chrome_browser_main_linux.h"
  #elif defined(OS_ANDROID)
  #include "chrome/browser/android/new_tab_page_url_handler.h"
  #include "chrome/browser/android/webapps/single_tab_mode_tab_helper.h"
  #include "chrome/browser/chrome_browser_main_android.h"
  #include "chrome/browser/media/protected_media_identifier_permission_context.h"
  #include "chrome/browser/media/protected_media_identifier_permission_context_factory.h"
  #include "chrome/common/descriptors_android.h"
  #include "components/crash/browser/crash_dump_manager_android.h"
  #elif defined(OS_POSIX)
  #include "chrome/browser/chrome_browser_main_posix.h"
  #endif
  
  #if defined(OS_POSIX) && !defined(OS_MACOSX)
  #include "base/debug/leak_annotations.h"
  #include "components/crash/app/breakpad_linux.h"
  #include "components/crash/browser/crash_handler_host_linux.h"
  #endif
  
  #if defined(OS_ANDROID)
  #include "ui/base/ui_base_paths.h"
  #include "ui/gfx/android/device_display_info.h"
  #endif
  
  #if defined(OS_ANDROID)
  #include "chrome/browser/android/dev_tools_manager_delegate_android.h"
  #else
  #include "chrome/browser/devtools/chrome_devtools_manager_delegate.h"
  #endif
  
  #if !defined(OS_CHROMEOS)
  #include "chrome/browser/signin/chrome_signin_client.h"
  #include "chrome/browser/signin/chrome_signin_client_factory.h"
  #include "chrome/browser/signin/signin_manager_factory.h"
  #include "components/signin/core/browser/signin_manager.h"
  #endif
  
  #if defined(TOOLKIT_VIEWS)
  #include "chrome/browser/ui/views/chrome_browser_main_extra_parts_views.h"
  #endif
  
  #if defined(USE_ATHENA)
  #include "athena/content/public/web_contents_view_delegate_creator.h"
  #include "chrome/browser/ui/views/athena/chrome_browser_main_extra_parts_athena.h"
  #elif defined(USE_ASH)
  #include "chrome/browser/ui/views/ash/chrome_browser_main_extra_parts_ash.h"
  #endif
  
  #if defined(USE_AURA)
  #include "chrome/browser/ui/aura/chrome_browser_main_extra_parts_aura.h"
  #endif
  
  #if defined(USE_X11)
  #include "chrome/browser/chrome_browser_main_extra_parts_x11.h"
  #endif
  
  #if defined(ENABLE_CAPTIVE_PORTAL_DETECTION)
  #include "chrome/browser/captive_portal/captive_portal_tab_helper.h"
  #endif
  
  #if !defined(DISABLE_NACL)
  #include "components/nacl/browser/nacl_browser.h"
  #include "components/nacl/browser/nacl_host_message_filter.h"
  #include "components/nacl/browser/nacl_process_host.h"
  #include "components/nacl/common/nacl_process_type.h"
  #include "components/nacl/common/nacl_switches.h"
  #endif
  
  #if defined(ENABLE_EXTENSIONS)
  #include "chrome/browser/extensions/chrome_content_browser_client_extensions_part.h"
  #include "chrome/browser/extensions/extension_util.h"
  #include "chrome/browser/speech/extension_api/tts_engine_extension_api.h"
  #include "extensions/browser/extension_registry.h"
  #include "extensions/browser/guest_view/guest_view_base.h"
  #include "extensions/browser/guest_view/guest_view_manager.h"
  #include "extensions/browser/guest_view/web_view/web_view_guest.h"
  #include "extensions/browser/guest_view/web_view/web_view_permission_helper.h"
  #include "extensions/browser/guest_view/web_view/web_view_renderer_state.h"
  #include "extensions/common/constants.h"
  #include "extensions/common/extension.h"
  #include "extensions/common/extension_set.h"
  #include "extensions/common/manifest_handlers/background_info.h"
  #include "extensions/common/manifest_handlers/shared_module_info.h"
  #include "extensions/common/permissions/permissions_data.h"
  #include "extensions/common/permissions/socket_permission.h"
  #include "extensions/common/switches.h"
  #endif
  
  #if defined(ENABLE_PLUGINS)
  #include "chrome/browser/plugins/chrome_content_browser_client_plugins_part.h"
  #endif
  
  #if defined(ENABLE_SPELLCHECK)
  #include "chrome/browser/spellchecker/spellcheck_message_filter.h"
  #endif
  
  #if defined(ENABLE_WEBRTC)
  #include "chrome/browser/media/webrtc_logging_handler_host.h"
  #endif
  
  using base::FileDescriptor;
  using blink::WebWindowFeatures;
  using content::AccessTokenStore;
  using content::BrowserThread;
  using content::BrowserURLHandler;
  using content::ChildProcessSecurityPolicy;
  using content::QuotaPermissionContext;
  using content::RenderFrameHost;
  using content::RenderViewHost;
  using content::ResourceType;
  using content::SiteInstance;
  using content::WebContents;
  using content::WebPreferences;
  using message_center::NotifierId;
  
  #if defined(OS_POSIX)
  using content::FileDescriptorInfo;
  #endif
  
  #if defined(ENABLE_EXTENSIONS)
  using extensions::APIPermission;
  using extensions::ChromeContentBrowserClientExtensionsPart;
  using extensions::Extension;
  using extensions::InfoMap;
  using extensions::Manifest;
  #endif
  
  #if defined(ENABLE_PLUGINS)
  using plugins::ChromeContentBrowserClientPluginsPart;
  #endif
  
  namespace {
  
  // Cached version of the locale so we can return the locale on the I/O
  // thread.
  base::LazyInstance<std::string> g_io_thread_application_locale;
  
  #if defined(ENABLE_PLUGINS)
  // TODO(teravest): Add renderer-side API-specific checking for these APIs so
  // that blanket permission isn't granted to all dev channel APIs for these.
  // http://crbug.com/386743
  const char* const kPredefinedAllowedDevChannelOrigins[] = {
    "6EAED1924DB611B6EEF2A664BD077BE7EAD33B8F",  // see crbug.com/383937
    "4EB74897CB187C7633357C2FE832E0AD6A44883A"   // see crbug.com/383937
  };
  
  const char* const kPredefinedAllowedFileHandleOrigins[] = {
    "6EAED1924DB611B6EEF2A664BD077BE7EAD33B8F",  // see crbug.com/234789
    "4EB74897CB187C7633357C2FE832E0AD6A44883A"   // see crbug.com/234789
  };
  
  const char* const kPredefinedAllowedSocketOrigins[] = {
    "okddffdblfhhnmhodogpojmfkjmhinfp",  // Test SSH Client
    "pnhechapfaindjhompbnflcldabbghjo",  // HTerm App (SSH Client)
    "bglhmjfplikpjnfoegeomebmfnkjomhe",  // see crbug.com/122126
    "gbchcmhmhahfdphkhkmpfmihenigjmpp",  // Chrome Remote Desktop
    "kgngmbheleoaphbjbaiobfdepmghbfah",  // Pre-release Chrome Remote Desktop
    "odkaodonbgfohohmklejpjiejmcipmib",  // Dogfood Chrome Remote Desktop
    "ojoimpklfciegopdfgeenehpalipignm",  // Chromoting canary
    "cbkkbcmdlboombapidmoeolnmdacpkch",  // see crbug.com/129089
    "hhnbmknkdabfoieppbbljkhkfjcmcbjh",  // see crbug.com/134099
    "mablfbjkhmhkmefkjjacnbaikjkipphg",  // see crbug.com/134099
    "pdeelgamlgannhelgoegilelnnojegoh",  // see crbug.com/134099
    "cabapfdbkniadpollkckdnedaanlciaj",  // see crbug.com/134099
    "mapljbgnjledlpdmlchihnmeclmefbba",  // see crbug.com/134099
    "ghbfeebgmiidnnmeobbbaiamklmpbpii",  // see crbug.com/134099
    "jdfhpkjeckflbbleddjlpimecpbjdeep",  // see crbug.com/142514
    "iabmpiboiopbgfabjmgeedhcmjenhbla",  // see crbug.com/165080
    "B7CF8A292249681AF81771650BA4CEEAF19A4560",  // see crbug.com/165080
    "7525AF4F66763A70A883C4700529F647B470E4D2",  // see crbug.com/238084
    "0B549507088E1564D672F7942EB87CA4DAD73972",  // see crbug.com/238084
    "864288364E239573E777D3E0E36864E590E95C74"   // see crbug.com/238084
  };
  #endif
  
  // Returns a copy of the given url with its host set to given host and path set
  // to given path. Other parts of the url will be the same.
  GURL ReplaceURLHostAndPath(const GURL& url,
                             const std::string& host,
                             const std::string& path) {
    url::Replacements<char> replacements;
    replacements.SetHost(host.c_str(), url::Component(0, host.length()));
    replacements.SetPath(path.c_str(), url::Component(0, path.length()));
    return url.ReplaceComponents(replacements);
  }
  
  // Maps "foo://bar/baz/" to "foo://chrome/bar/baz/".
  GURL AddUberHost(const GURL& url) {
    const std::string uber_host = chrome::kChromeUIUberHost;
    const std::string new_path = url.host() + url.path();
  
    return ReplaceURLHostAndPath(url, uber_host, new_path);
  }
  
  // If url->host() is "chrome" and url->path() has characters other than the
  // first slash, changes the url from "foo://chrome/bar/" to "foo://bar/" and
  // returns true. Otherwise returns false.
  bool RemoveUberHost(GURL* url) {
    if (url->host() != chrome::kChromeUIUberHost)
      return false;
  
    if (url->path().empty() || url->path() == "/")
      return false;
  
    const std::string old_path = url->path();
  
    const std::string::size_type separator = old_path.find('/', 1);
    std::string new_host;
    std::string new_path;
    if (separator == std::string::npos) {
      new_host = old_path.substr(1);
    } else {
      new_host = old_path.substr(1, separator - 1);
      new_path = old_path.substr(separator);
    }
  
    // Do not allow URLs with paths empty before the first slash since we can't
    // have an empty host. (e.g "foo://chrome//")
    if (new_host.empty())
      return false;
  
    *url = ReplaceURLHostAndPath(*url, new_host, new_path);
  
    DCHECK(url->is_valid());
  
    return true;
  }
  
  // Handles rewriting Web UI URLs.
  bool HandleWebUI(GURL* url, content::BrowserContext* browser_context) {
    // Do not handle special URLs such as "about:foo"
    if (!url->host().empty()) {
      const GURL chrome_url = AddUberHost(*url);
  
      // Handle valid "chrome://chrome/foo" URLs so the reverse handler will
      // be called.
      if (ChromeWebUIControllerFactory::GetInstance()->UseWebUIForURL(
              browser_context, chrome_url))
        return true;
    }
  
    if (!ChromeWebUIControllerFactory::GetInstance()->UseWebUIForURL(
            browser_context, *url))
      return false;
  
  #if defined(OS_CHROMEOS)
    // Special case : in ChromeOS in Guest mode bookmarks and history are
    // disabled for security reasons. New tab page explains the reasons, so
    // we redirect user to new tab page.
    if (user_manager::UserManager::Get()->IsLoggedInAsGuest()) {
      if (url->SchemeIs(content::kChromeUIScheme) &&
          (url->DomainIs(chrome::kChromeUIBookmarksHost) ||
           url->DomainIs(chrome::kChromeUIHistoryHost))) {
        // Rewrite with new tab URL
        *url = GURL(chrome::kChromeUINewTabURL);
      }
    }
  #endif
  
    return true;
  }
  
  // Reverse URL handler for Web UI. Maps "chrome://chrome/foo/" to
  // "chrome://foo/".
  bool HandleWebUIReverse(GURL* url, content::BrowserContext* browser_context) {
    if (!url->is_valid() || !url->SchemeIs(content::kChromeUIScheme))
      return false;
  
    return RemoveUberHost(url);
  }
  
  bool CertMatchesFilter(const net::X509Certificate& cert,
                         const base::DictionaryValue& filter) {
    // TODO(markusheintz): This is the minimal required filter implementation.
    // Implement a better matcher.
  
    // An empty filter matches any client certificate since no requirements are
    // specified at all.
    if (filter.empty())
      return true;
  
    std::string common_name;
    if (filter.GetString("ISSUER.CN", &common_name) &&
        (cert.issuer().common_name == common_name)) {
      return true;
    }
    return false;
  }
  
  #if defined(OS_POSIX) && !defined(OS_ANDROID) && !defined(OS_MACOSX)
  breakpad::CrashHandlerHostLinux* CreateCrashHandlerHost(
      const std::string& process_type) {
    base::FilePath dumps_path;
    PathService::Get(chrome::DIR_CRASH_DUMPS, &dumps_path);
    {
      ANNOTATE_SCOPED_MEMORY_LEAK;
      bool upload = (getenv(env_vars::kHeadless) == NULL);
      breakpad::CrashHandlerHostLinux* crash_handler =
          new breakpad::CrashHandlerHostLinux(process_type, dumps_path, upload);
      crash_handler->StartUploaderThread();
      return crash_handler;
    }
  }
  
  int GetCrashSignalFD(const base::CommandLine& command_line) {
    // Extensions have the same process type as renderers.
    if (command_line.HasSwitch(extensions::switches::kExtensionProcess)) {
      static breakpad::CrashHandlerHostLinux* crash_handler = NULL;
      if (!crash_handler)
        crash_handler = CreateCrashHandlerHost("extension");
      return crash_handler->GetDeathSignalSocket();
    }
  
    std::string process_type =
        command_line.GetSwitchValueASCII(switches::kProcessType);
  
    if (process_type == switches::kRendererProcess) {
      static breakpad::CrashHandlerHostLinux* crash_handler = NULL;
      if (!crash_handler)
        crash_handler = CreateCrashHandlerHost(process_type);
      return crash_handler->GetDeathSignalSocket();
    }
  
    if (process_type == switches::kPluginProcess) {
      static breakpad::CrashHandlerHostLinux* crash_handler = NULL;
      if (!crash_handler)
        crash_handler = CreateCrashHandlerHost(process_type);
      return crash_handler->GetDeathSignalSocket();
    }
  
    if (process_type == switches::kPpapiPluginProcess) {
      static breakpad::CrashHandlerHostLinux* crash_handler = NULL;
      if (!crash_handler)
        crash_handler = CreateCrashHandlerHost(process_type);
      return crash_handler->GetDeathSignalSocket();
    }
  
    if (process_type == switches::kGpuProcess) {
      static breakpad::CrashHandlerHostLinux* crash_handler = NULL;
      if (!crash_handler)
        crash_handler = CreateCrashHandlerHost(process_type);
      return crash_handler->GetDeathSignalSocket();
    }
  
    return -1;
  }
  #endif  // defined(OS_POSIX) && !defined(OS_ANDROID) && !defined(OS_MACOSX)
  
  #if !defined(OS_CHROMEOS)
  GURL GetEffectiveURLForSignin(const GURL& url) {
    CHECK(SigninManager::IsWebBasedSigninFlowURL(url));
  
    GURL effective_url(SigninManager::kChromeSigninEffectiveSite);
    // Copy the path because the argument to SetPathStr must outlive
    // the Replacements object.
    const std::string path_copy(url.path());
    GURL::Replacements replacements;
    replacements.SetPathStr(path_copy);
    effective_url = effective_url.ReplaceComponents(replacements);
    return effective_url;
  }
  #endif
  
  void SetApplicationLocaleOnIOThread(const std::string& locale) {
    DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
    g_io_thread_application_locale.Get() = locale;
  }
  
  void HandleBlockedPopupOnUIThread(const BlockedWindowParams& params) {
    // TODO(jochen): This code path should use RenderFrameHosts. See
    // http://crbug.com/431769 for details.
    RenderViewHost* render_view_host =
        RenderViewHost::FromID(params.render_process_id(), params.opener_id());
    if (!render_view_host)
      return;
    WebContents* tab = WebContents::FromRenderViewHost(render_view_host);
    // The tab might already have navigated away.
    if (!tab || tab->GetRenderViewHost() != render_view_host)
      return;
  
    prerender::PrerenderContents* prerender_contents =
        prerender::PrerenderContents::FromWebContents(tab);
    if (prerender_contents) {
      prerender_contents->Destroy(prerender::FINAL_STATUS_CREATE_NEW_WINDOW);
      return;
    }
  
    PopupBlockerTabHelper* popup_helper =
        PopupBlockerTabHelper::FromWebContents(tab);
    if (!popup_helper)
      return;
    popup_helper->AddBlockedPopup(params);
  }
  
  #if defined(OS_ANDROID)
  
  void HandleSingleTabModeBlockOnUIThread(const BlockedWindowParams& params) {
    WebContents* web_contents =
        tab_util::GetWebContentsByID(params.render_process_id(),
                                     params.opener_id());
    if (!web_contents)
      return;
  
    SingleTabModeTabHelper::FromWebContents(web_contents)->HandleOpenUrl(params);
  }
  
  float GetDeviceScaleAdjustment() {
    static const float kMinFSM = 1.05f;
    static const int kWidthForMinFSM = 320;
    static const float kMaxFSM = 1.3f;
    static const int kWidthForMaxFSM = 800;
  
    gfx::DeviceDisplayInfo info;
    int minWidth = info.GetSmallestDIPWidth();
  
    if (minWidth <= kWidthForMinFSM)
      return kMinFSM;
    if (minWidth >= kWidthForMaxFSM)
      return kMaxFSM;
  
    // The font scale multiplier varies linearly between kMinFSM and kMaxFSM.
    float ratio = static_cast<float>(minWidth - kWidthForMinFSM) /
        (kWidthForMaxFSM - kWidthForMinFSM);
    return ratio * (kMaxFSM - kMinFSM) + kMinFSM;
  }
  
  #endif  // defined(OS_ANDROID)
  
  #if defined(ENABLE_EXTENSIONS)
  // By default, JavaScript and images are enabled in guest content.
  void GetGuestViewDefaultContentSettingRules(
      bool incognito,
      RendererContentSettingRules* rules) {
    rules->image_rules.push_back(
        ContentSettingPatternSource(ContentSettingsPattern::Wildcard(),
                                    ContentSettingsPattern::Wildcard(),
                                    CONTENT_SETTING_ALLOW,
                                    std::string(),
                                    incognito));
  
    rules->script_rules.push_back(
        ContentSettingPatternSource(ContentSettingsPattern::Wildcard(),
                                    ContentSettingsPattern::Wildcard(),
                                    CONTENT_SETTING_ALLOW,
                                    std::string(),
                                    incognito));
  }
  #endif  // defined(ENALBE_EXTENSIONS)
  
  content::PermissionStatus
  ContentSettingToPermissionStatus(ContentSetting setting) {
    switch (setting) {
      case CONTENT_SETTING_ALLOW:
      case CONTENT_SETTING_SESSION_ONLY:
        return content::PERMISSION_STATUS_GRANTED;
      case CONTENT_SETTING_BLOCK:
        return content::PERMISSION_STATUS_DENIED;
      case CONTENT_SETTING_ASK:
        return content::PERMISSION_STATUS_ASK;
      case CONTENT_SETTING_DETECT_IMPORTANT_CONTENT:
      case CONTENT_SETTING_DEFAULT:
      case CONTENT_SETTING_NUM_SETTINGS:
        break;
    }
    NOTREACHED();
    return content::PERMISSION_STATUS_DENIED;
  }
  
  }  // namespace
  
  namespace chrome {
  
  ChromeContentBrowserClient::ChromeContentBrowserClient()
      : prerender_tracker_(NULL),
        weak_factory_(this) {
  #if defined(ENABLE_PLUGINS)
    for (size_t i = 0; i < arraysize(kPredefinedAllowedDevChannelOrigins); ++i)
      allowed_dev_channel_origins_.insert(kPredefinedAllowedDevChannelOrigins[i]);
    for (size_t i = 0; i < arraysize(kPredefinedAllowedFileHandleOrigins); ++i)
      allowed_file_handle_origins_.insert(kPredefinedAllowedFileHandleOrigins[i]);
    for (size_t i = 0; i < arraysize(kPredefinedAllowedSocketOrigins); ++i)
      allowed_socket_origins_.insert(kPredefinedAllowedSocketOrigins[i]);
  
    extra_parts_.push_back(new ChromeContentBrowserClientPluginsPart);
  #endif
  
  #if !defined(OS_ANDROID)
    TtsExtensionEngine* tts_extension_engine = TtsExtensionEngine::GetInstance();
    TtsController::GetInstance()->SetTtsEngineDelegate(tts_extension_engine);
  #endif
  
  #if defined(ENABLE_EXTENSIONS)
    extra_parts_.push_back(new ChromeContentBrowserClientExtensionsPart);
  #endif
  }
  
  ChromeContentBrowserClient::~ChromeContentBrowserClient() {
    for (int i = static_cast<int>(extra_parts_.size()) - 1; i >= 0; --i)
      delete extra_parts_[i];
    extra_parts_.clear();
  }
  
  // static
  void ChromeContentBrowserClient::RegisterProfilePrefs(
      user_prefs::PrefRegistrySyncable* registry) {
    registry->RegisterBooleanPref(
        prefs::kDisable3DAPIs,
        false,
        user_prefs::PrefRegistrySyncable::UNSYNCABLE_PREF);
    registry->RegisterBooleanPref(
        prefs::kEnableHyperlinkAuditing,
        true,
        user_prefs::PrefRegistrySyncable::UNSYNCABLE_PREF);
    registry->RegisterListPref(
        prefs::kEnableDeprecatedWebPlatformFeatures,
        user_prefs::PrefRegistrySyncable::UNSYNCABLE_PREF);
  }
  
  // static
  void ChromeContentBrowserClient::SetApplicationLocale(
      const std::string& locale) {
    DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
  
    // This object is guaranteed to outlive all threads so we don't have to
    // worry about the lack of refcounting and can just post as Unretained.
    //
    // The common case is that this function is called early in Chrome startup
    // before any threads are created (it will also be called later if the user
    // changes the pref). In this case, there will be no threads created and
    // posting will fail. When there are no threads, we can just set the string
    // without worrying about threadsafety.
    if (!BrowserThread::PostTask(BrowserThread::IO, FROM_HERE,
            base::Bind(&SetApplicationLocaleOnIOThread, locale))) {
      g_io_thread_application_locale.Get() = locale;
    }
  }
  
  content::BrowserMainParts* ChromeContentBrowserClient::CreateBrowserMainParts(
      const content::MainFunctionParams& parameters) {
    ChromeBrowserMainParts* main_parts;
    // Construct the Main browser parts based on the OS type.
  #if defined(OS_WIN)
    main_parts = new ChromeBrowserMainPartsWin(parameters);
  #elif defined(OS_MACOSX)
    main_parts = new ChromeBrowserMainPartsMac(parameters);
  #elif defined(OS_CHROMEOS)
    main_parts = new chromeos::ChromeBrowserMainPartsChromeos(parameters);
  #elif defined(OS_LINUX)
    main_parts = new ChromeBrowserMainPartsLinux(parameters);
  #elif defined(OS_ANDROID)
    main_parts = new ChromeBrowserMainPartsAndroid(parameters);
  #elif defined(OS_POSIX)
    main_parts = new ChromeBrowserMainPartsPosix(parameters);
  #else
    NOTREACHED();
    main_parts = new ChromeBrowserMainParts(parameters);
  #endif
  
    chrome::AddProfilesExtraParts(main_parts);
  
    // Construct additional browser parts. Stages are called in the order in
    // which they are added.
  #if defined(TOOLKIT_VIEWS)
    main_parts->AddParts(new ChromeBrowserMainExtraPartsViews());
  #endif
  
  // TODO(oshima): Athena on chrome currently requires USE_ASH to build.
  // We should reduce the dependency as much as possible.
  #if defined(USE_ATHENA)
    main_parts->AddParts(CreateChromeBrowserMainExtraPartsAthena());
  #elif defined(USE_ASH)
    main_parts->AddParts(new ChromeBrowserMainExtraPartsAsh());
  #endif
  
  #if defined(USE_AURA)
    main_parts->AddParts(new ChromeBrowserMainExtraPartsAura());
  #endif
  
  #if defined(USE_X11)
    main_parts->AddParts(new ChromeBrowserMainExtraPartsX11());
  #endif
  
    chrome::AddMetricsExtraParts(main_parts);
  
    return main_parts;
  }
  
  std::string ChromeContentBrowserClient::GetStoragePartitionIdForSite(
      content::BrowserContext* browser_context,
      const GURL& site) {
    std::string partition_id;
  
    // The partition ID for webview guest processes is the string value of its
    // SiteInstance URL - "chrome-guest://app_id/persist?partition".
    if (site.SchemeIs(content::kGuestScheme)) {
      partition_id = site.spec();
    } else if (site.GetOrigin().spec() == kChromeUIChromeSigninURL &&
              !switches::IsEnableWebviewBasedSignin()) {
      // Chrome signin page has an embedded iframe of extension and web content,
      // thus it must be isolated from other webUI pages.
      partition_id = site.GetOrigin().spec();
    }
  
    DCHECK(IsValidStoragePartitionId(browser_context, partition_id));
    return partition_id;
  }
  
  bool ChromeContentBrowserClient::IsValidStoragePartitionId(
      content::BrowserContext* browser_context,
      const std::string& partition_id) {
    // The default ID is empty and is always valid.
    if (partition_id.empty())
      return true;
  
    return GURL(partition_id).is_valid();
  }
  
  void ChromeContentBrowserClient::GetStoragePartitionConfigForSite(
      content::BrowserContext* browser_context,
      const GURL& site,
      bool can_be_default,
      std::string* partition_domain,
      std::string* partition_name,
      bool* in_memory) {
    // Default to the browser-wide storage partition and override based on |site|
    // below.
    partition_domain->clear();
    partition_name->clear();
    *in_memory = false;
  
    bool success = false;
  #if defined(ENABLE_EXTENSIONS)
    success = extensions::WebViewGuest::GetGuestPartitionConfigForSite(
        site, partition_domain, partition_name, in_memory);
  
    if (!success && site.SchemeIs(extensions::kExtensionScheme)) {
      // If |can_be_default| is false, the caller is stating that the |site|
      // should be parsed as if it had isolated storage. In particular it is
      // important to NOT check ExtensionService for the is_storage_isolated()
      // attribute because this code path is run during Extension uninstall
      // to do cleanup after the Extension has already been unloaded from the
      // ExtensionService.
      bool is_isolated = !can_be_default;
      if (can_be_default) {
        if (extensions::util::SiteHasIsolatedStorage(site, browser_context))
          is_isolated = true;
      }
  
      if (is_isolated) {
        CHECK(site.has_host());
        // For extensions with isolated storage, the the host of the |site| is
        // the |partition_domain|. The |in_memory| and |partition_name| are only
        // used in guest schemes so they are cleared here.
        *partition_domain = site.host();
        *in_memory = false;
        partition_name->clear();
      }
      success = true;
    }
  #endif
  
    if (!success && (site.GetOrigin().spec() == kChromeUIChromeSigninURL) &&
        !switches::IsEnableWebviewBasedSignin()) {
      // Chrome signin page has an embedded iframe of extension and web content,
      // thus it must be isolated from other webUI pages.
      *partition_domain = chrome::kChromeUIChromeSigninHost;
    }
  
    // Assert that if |can_be_default| is false, the code above must have found a
    // non-default partition.  If this fails, the caller has a serious logic
    // error about which StoragePartition they expect to be in and it is not
    // safe to continue.
    CHECK(can_be_default || !partition_domain->empty());
  }
  
  content::WebContentsViewDelegate*
      ChromeContentBrowserClient::GetWebContentsViewDelegate(
          content::WebContents* web_contents) {
  #if defined(USE_ATHENA)
    return athena::CreateWebContentsViewDelegate(web_contents);
  #else
    return chrome::CreateWebContentsViewDelegate(web_contents);
  #endif
  }
  
  void ChromeContentBrowserClient::RenderProcessWillLaunch(
      content::RenderProcessHost* host) {
    int id = host->GetID();
    Profile* profile = Profile::FromBrowserContext(host->GetBrowserContext());
    net::URLRequestContextGetter* context =
        profile->GetRequestContextForRenderProcess(id);
  
    host->AddFilter(new ChromeRenderMessageFilter(id, profile));
    host->AddFilter(new cast::CastTransportHostFilter);
  #if defined(ENABLE_PRINTING)
    host->AddFilter(new printing::PrintingMessageFilter(id, profile));
  #endif
    host->AddFilter(new SearchProviderInstallStateMessageFilter(id, profile));
  #if defined(ENABLE_SPELLCHECK)
    host->AddFilter(new SpellCheckMessageFilter(id));
  #endif
  #if defined(OS_MACOSX)
    host->AddFilter(new SpellCheckMessageFilterMac(id));
  #endif
    host->AddFilter(new ChromeNetBenchmarkingMessageFilter(profile, context));
    host->AddFilter(new prerender::PrerenderMessageFilter(id, profile));
    host->AddFilter(new TtsMessageFilter(id, host->GetBrowserContext()));
  #if defined(ENABLE_WEBRTC)
    WebRtcLoggingHandlerHost* webrtc_logging_handler_host =
        new WebRtcLoggingHandlerHost(profile);
    host->SetWebRtcLogMessageCallback(base::Bind(
        &WebRtcLoggingHandlerHost::LogMessage, webrtc_logging_handler_host));
    host->AddFilter(webrtc_logging_handler_host);
    host->SetUserData(host, new base::UserDataAdapter<WebRtcLoggingHandlerHost>(
        webrtc_logging_handler_host));
  #endif
  #if !defined(DISABLE_NACL)
    host->AddFilter(new nacl::NaClHostMessageFilter(
        id, profile->IsOffTheRecord(),
        profile->GetPath(),
        context));
  #endif
  #if defined(OS_ANDROID)
    host->AddFilter(new cdm::CdmMessageFilterAndroid());
  #endif
    if (switches::IsEnableAccountConsistency())
      host->AddFilter(new PrincipalsMessageFilter(id));
  
    host->Send(new ChromeViewMsg_SetIsIncognitoProcess(
        profile->IsOffTheRecord()));
  
    for (size_t i = 0; i < extra_parts_.size(); ++i)
      extra_parts_[i]->RenderProcessWillLaunch(host);
  
    RendererContentSettingRules rules;
    if (host->IsIsolatedGuest()) {
  #if defined(ENABLE_EXTENSIONS)
      GetGuestViewDefaultContentSettingRules(profile->IsOffTheRecord(), &rules);
  #else
      NOTREACHED();
  #endif
    } else {
      GetRendererContentSettingRules(
          profile->GetHostContentSettingsMap(), &rules);
    }
    host->Send(new ChromeViewMsg_SetContentSettingRules(rules));
  }
  
  GURL ChromeContentBrowserClient::GetEffectiveURL(
      content::BrowserContext* browser_context, const GURL& url) {
    Profile* profile = Profile::FromBrowserContext(browser_context);
    if (!profile)
      return url;
  
    // If the input |url| should be assigned to the Instant renderer, make its
    // effective URL distinct from other URLs on the search provider's domain.
    if (chrome::ShouldAssignURLToInstantRenderer(url, profile))
      return chrome::GetEffectiveURLForInstant(url, profile);
  
  #if !defined(OS_CHROMEOS)
    // If the input |url| should be assigned to the Signin renderer, make its
    // effective URL distinct from other URLs on the signin service's domain.
    // Note that the signin renderer will be allowed to sign the user in to
    // Chrome.
    if (SigninManager::IsWebBasedSigninFlowURL(url))
      return GetEffectiveURLForSignin(url);
  #endif
  
  #if defined(ENABLE_EXTENSIONS)
    return ChromeContentBrowserClientExtensionsPart::GetEffectiveURL(
        profile, url);
  #else
    return url;
  #endif
  }
  
  bool ChromeContentBrowserClient::ShouldUseProcessPerSite(
      content::BrowserContext* browser_context, const GURL& effective_url) {
    // Non-extension, non-Instant URLs should generally use
    // process-per-site-instance.  Because we expect to use the effective URL,
    // URLs for hosted apps (apart from bookmark apps) should have an extension
    // scheme by now.
  
    Profile* profile = Profile::FromBrowserContext(browser_context);
    if (!profile)
      return false;
  
    if (chrome::ShouldUseProcessPerSiteForInstantURL(effective_url, profile))
      return true;
  
  #if !defined(OS_CHROMEOS)
    if (SigninManager::IsWebBasedSigninFlowURL(effective_url))
      return true;
  #endif
  
  #if defined(ENABLE_EXTENSIONS)
    return ChromeContentBrowserClientExtensionsPart::ShouldUseProcessPerSite(
        profile, effective_url);
  #else
    return false;
  #endif
  }
  
  // These are treated as WebUI schemes but do not get WebUI bindings. Also,
  // view-source is allowed for these schemes.
  void ChromeContentBrowserClient::GetAdditionalWebUISchemes(
      std::vector<std::string>* additional_schemes) {
    additional_schemes->push_back(chrome::kChromeSearchScheme);
    additional_schemes->push_back(dom_distiller::kDomDistillerScheme);
  }
  
  void ChromeContentBrowserClient::GetAdditionalWebUIHostsToIgnoreParititionCheck(
      std::vector<std::string>* hosts) {
    hosts->push_back(chrome::kChromeUIExtensionIconHost);
    hosts->push_back(chrome::kChromeUIFaviconHost);
    hosts->push_back(chrome::kChromeUIThemeHost);
    hosts->push_back(chrome::kChromeUIThumbnailHost);
    hosts->push_back(chrome::kChromeUIThumbnailHost2);
    hosts->push_back(chrome::kChromeUIThumbnailListHost);
  }
  
  net::URLRequestContextGetter*
  ChromeContentBrowserClient::CreateRequestContext(
      content::BrowserContext* browser_context,
      content::ProtocolHandlerMap* protocol_handlers,
      content::URLRequestInterceptorScopedVector request_interceptors) {
    Profile* profile = Profile::FromBrowserContext(browser_context);
    return profile->CreateRequestContext(protocol_handlers,
                                         request_interceptors.Pass());
  }
  
  net::URLRequestContextGetter*
  ChromeContentBrowserClient::CreateRequestContextForStoragePartition(
      content::BrowserContext* browser_context,
      const base::FilePath& partition_path,
      bool in_memory,
      content::ProtocolHandlerMap* protocol_handlers,
      content::URLRequestInterceptorScopedVector request_interceptors) {
    Profile* profile = Profile::FromBrowserContext(browser_context);
    return profile->CreateRequestContextForStoragePartition(
        partition_path,
        in_memory,
        protocol_handlers,
        request_interceptors.Pass());
  }
  
  bool ChromeContentBrowserClient::IsHandledURL(const GURL& url) {
    return ProfileIOData::IsHandledURL(url);
  }
  
  bool ChromeContentBrowserClient::CanCommitURL(
      content::RenderProcessHost* process_host,
      const GURL& url) {
  #if defined(ENABLE_EXTENSIONS)
    return ChromeContentBrowserClientExtensionsPart::CanCommitURL(
        process_host, url);
  #else
    return true;
  #endif
  }
  
  bool ChromeContentBrowserClient::ShouldAllowOpenURL(
      content::SiteInstance* site_instance, const GURL& url) {
    GURL from_url = site_instance->GetSiteURL();
  
  #if defined(ENABLE_EXTENSIONS)
    bool result;
    if (ChromeContentBrowserClientExtensionsPart::ShouldAllowOpenURL(
        site_instance, from_url, url, &result))
      return result;
  #endif
  
    // Do not allow chrome://chrome-signin navigate to other chrome:// URLs, since
    // the signin page may host untrusted web content.
    if (from_url.GetOrigin().spec() == chrome::kChromeUIChromeSigninURL &&
        url.SchemeIs(content::kChromeUIScheme) &&
        url.host() != chrome::kChromeUIChromeSigninHost) {
      VLOG(1) << "Blocked navigation to " << url.spec() << " from "
              << chrome::kChromeUIChromeSigninURL;
      return false;
    }
  
    return true;
  }
  
  bool ChromeContentBrowserClient::IsSuitableHost(
      content::RenderProcessHost* process_host,
      const GURL& site_url) {
    Profile* profile =
        Profile::FromBrowserContext(process_host->GetBrowserContext());
    // This may be NULL during tests. In that case, just assume any site can
    // share any host.
    if (!profile)
      return true;
  
    // Instant URLs should only be in the instant process and instant process
    // should only have Instant URLs.
    InstantService* instant_service =
        InstantServiceFactory::GetForProfile(profile);
    if (instant_service) {
      bool is_instant_process = instant_service->IsInstantProcess(
          process_host->GetID());
      bool should_be_in_instant_process =
          chrome::ShouldAssignURLToInstantRenderer(site_url, profile);
      if (is_instant_process || should_be_in_instant_process)
        return is_instant_process && should_be_in_instant_process;
    }
  
  #if !defined(OS_CHROMEOS)
    SigninClient* signin_client =
        ChromeSigninClientFactory::GetForProfile(profile);
    if (signin_client && signin_client->IsSigninProcess(process_host->GetID()))
      return SigninManager::IsWebBasedSigninFlowURL(site_url);
  #endif
  
  #if defined(ENABLE_EXTENSIONS)
    return ChromeContentBrowserClientExtensionsPart::IsSuitableHost(
        profile, process_host, site_url);
  #else
    return true;
  #endif
  }
  
  bool ChromeContentBrowserClient::MayReuseHost(
      content::RenderProcessHost* process_host) {
    // If there is currently a prerender in progress for the host provided,
    // it may not be shared. We require prerenders to be by themselves in a
    // separate process, so that we can monitor their resource usage, and so that
    // we can track the cookies that they change.
    Profile* profile = Profile::FromBrowserContext(
        process_host->GetBrowserContext());
    prerender::PrerenderManager* prerender_manager =
        prerender::PrerenderManagerFactory::GetForProfile(profile);
    if (prerender_manager &&
        !prerender_manager->MayReuseProcessHost(process_host)) {
      return false;
    }
  
    return true;
  }
  
  bool ChromeContentBrowserClient::ShouldTryToUseExistingProcessHost(
      content::BrowserContext* browser_context, const GURL& url) {
    // It has to be a valid URL for us to check for an extension.
    if (!url.is_valid())
      return false;
  
  #if defined(ENABLE_EXTENSIONS)
    Profile* profile = Profile::FromBrowserContext(browser_context);
    return ChromeContentBrowserClientExtensionsPart::
        ShouldTryToUseExistingProcessHost(
            profile, url);
  #else
    return false;
  #endif
  }
  
  void ChromeContentBrowserClient::SiteInstanceGotProcess(
      SiteInstance* site_instance) {
    CHECK(site_instance->HasProcess());
  
    Profile* profile = Profile::FromBrowserContext(
        site_instance->GetBrowserContext());
    if (!profile)
      return;
  
    // Remember the ID of the Instant process to signal the renderer process
    // on startup in |AppendExtraCommandLineSwitches| below.
    if (chrome::ShouldAssignURLToInstantRenderer(
            site_instance->GetSiteURL(), profile)) {
      InstantService* instant_service =
          InstantServiceFactory::GetForProfile(profile);
      if (instant_service)
        instant_service->AddInstantProcess(site_instance->GetProcess()->GetID());
    }
  
  #if !defined(OS_CHROMEOS)
    // We only expect there to be one signin process as we use process-per-site
    // for signin URLs. The signin process will be cleared from SigninManager
    // when the renderer is destroyed.
    if (SigninManager::IsWebBasedSigninFlowURL(site_instance->GetSiteURL())) {
      SigninClient* signin_client =
          ChromeSigninClientFactory::GetForProfile(profile);
      if (signin_client)
        signin_client->SetSigninProcess(site_instance->GetProcess()->GetID());
  #if defined(ENABLE_EXTENSIONS)
      ChromeContentBrowserClientExtensionsPart::SetSigninProcess(site_instance);
  #endif
    }
  #endif
  
    for (size_t i = 0; i < extra_parts_.size(); ++i)
      extra_parts_[i]->SiteInstanceGotProcess(site_instance);
  }
  
  void ChromeContentBrowserClient::SiteInstanceDeleting(
      SiteInstance* site_instance) {
    if (!site_instance->HasProcess())
      return;
  
    for (size_t i = 0; i < extra_parts_.size(); ++i)
      extra_parts_[i]->SiteInstanceDeleting(site_instance);
  }
  
  bool ChromeContentBrowserClient::ShouldSwapBrowsingInstancesForNavigation(
      SiteInstance* site_instance,
      const GURL& current_url,
      const GURL& new_url) {
  #if defined(ENABLE_EXTENSIONS)
    return ChromeContentBrowserClientExtensionsPart::
        ShouldSwapBrowsingInstancesForNavigation(
            site_instance, current_url, new_url);
  #else
    return false;
  #endif
  }
  
  bool ChromeContentBrowserClient::ShouldSwapProcessesForRedirect(
      content::ResourceContext* resource_context, const GURL& current_url,
      const GURL& new_url) {
  #if defined(ENABLE_EXTENSIONS)
    return ChromeContentBrowserClientExtensionsPart::
        ShouldSwapProcessesForRedirect(resource_context, current_url, new_url);
  #else
    return false;
  #endif
  }
  
  bool ChromeContentBrowserClient::ShouldAssignSiteForURL(const GURL& url) {
    return !url.SchemeIs(chrome::kChromeNativeScheme);
  }
  
  std::string ChromeContentBrowserClient::GetCanonicalEncodingNameByAliasName(
      const std::string& alias_name) {
    return CharacterEncoding::GetCanonicalEncodingNameByAliasName(alias_name);
  }
  
  namespace {
  
  bool IsAutoReloadEnabled() {
    // Fetch the field trial, even though we don't use it. Calling FindFullName()
    // causes the field-trial mechanism to report which group we're in, which
    // might reflect a hard disable or hard enable via flag, both of which have
    // their own field trial groups. This lets us know what percentage of users
    // manually enable or disable auto-reload.
    std::string group = base::FieldTrialList::FindFullName(
        "AutoReloadExperiment");
    const base::CommandLine& browser_command_line =
        *base::CommandLine::ForCurrentProcess();
    if (browser_command_line.HasSwitch(switches::kEnableOfflineAutoReload))
      return true;
    if (browser_command_line.HasSwitch(switches::kDisableOfflineAutoReload))
      return false;
    return true;
  }
  
  bool IsAutoReloadVisibleOnlyEnabled() {
    // See the block comment in IsAutoReloadEnabled().
    std::string group = base::FieldTrialList::FindFullName(
        "AutoReloadVisibleOnlyExperiment");
    const base::CommandLine& browser_command_line =
        *base::CommandLine::ForCurrentProcess();
    if (browser_command_line.HasSwitch(
        switches::kEnableOfflineAutoReloadVisibleOnly)) {
      return true;
    }
    if (browser_command_line.HasSwitch(
        switches::kDisableOfflineAutoReloadVisibleOnly)) {
      return false;
    }
    return true;
  }
  
  }  // namespace
  
  void ChromeContentBrowserClient::AppendExtraCommandLineSwitches(
      base::CommandLine* command_line,
      int child_process_id) {
  #if defined(OS_POSIX)
    if (breakpad::IsCrashReporterEnabled()) {
      scoped_ptr<metrics::ClientInfo> client_info =
          GoogleUpdateSettings::LoadMetricsClientInfo();
      command_line->AppendSwitchASCII(switches::kEnableCrashReporter,
                                      client_info ? client_info->client_id
                                                  : std::string());
    }
  #endif  // defined(OS_POSIX)
  
    if (logging::DialogsAreSuppressed())
      command_line->AppendSwitch(switches::kNoErrorDialogs);
  
    std::string process_type =
        command_line->GetSwitchValueASCII(switches::kProcessType);
    const base::CommandLine& browser_command_line =
        *base::CommandLine::ForCurrentProcess();
  
    static const char* const kCommonSwitchNames[] = {
      switches::kUserAgent,
      switches::kUserDataDir,  // Make logs go to the right file.
    };
    command_line->CopySwitchesFrom(browser_command_line, kCommonSwitchNames,
                                   arraysize(kCommonSwitchNames));
  
  #if defined(ENABLE_IPC_FUZZER)
    static const char* const kIpcFuzzerSwitches[] = {
      switches::kIpcFuzzerTestcase,
    };
    command_line->CopySwitchesFrom(browser_command_line, kIpcFuzzerSwitches,
                                   arraysize(kIpcFuzzerSwitches));
  #endif
  
  #if defined(OS_CHROMEOS)
    // On Chrome OS need to pass primary user homedir (in multi-profiles session).
    base::FilePath homedir;
    PathService::Get(base::DIR_HOME, &homedir);
    command_line->AppendSwitchASCII(chromeos::switches::kHomedir,
                                    homedir.value().c_str());
  #endif
  
    if (process_type == switches::kRendererProcess) {
      content::RenderProcessHost* process =
          content::RenderProcessHost::FromID(child_process_id);
      Profile* profile =
          process ? Profile::FromBrowserContext(process->GetBrowserContext())
                  : NULL;
      for (size_t i = 0; i < extra_parts_.size(); ++i) {
        extra_parts_[i]->AppendExtraRendererCommandLineSwitches(
            command_line, process, profile);
      }
  
  #if defined(OS_CHROMEOS)
      const std::string& login_profile =
          browser_command_line.GetSwitchValueASCII(
              chromeos::switches::kLoginProfile);
      if (!login_profile.empty())
        command_line->AppendSwitchASCII(
            chromeos::switches::kLoginProfile, login_profile);
  #endif
  
  #if defined(ENABLE_WEBRTC)
      MaybeCopyDisableWebRtcEncryptionSwitch(command_line,
                                             browser_command_line,
                                             VersionInfo::GetChannel());
  #endif
  
      if (process) {
        PrefService* prefs = profile->GetPrefs();
        // Currently this pref is only registered if applied via a policy.
        if (prefs->HasPrefPath(prefs::kDisable3DAPIs) &&
            prefs->GetBoolean(prefs::kDisable3DAPIs)) {
          // Turn this policy into a command line switch.
          command_line->AppendSwitch(switches::kDisable3DAPIs);
        }
  
        const base::ListValue* switches =
            prefs->GetList(prefs::kEnableDeprecatedWebPlatformFeatures);
        if (switches) {
          // Enable any deprecated features that have been re-enabled by policy.
          for (base::ListValue::const_iterator it = switches->begin();
               it != switches->end(); ++it) {
            std::string switch_to_enable;
            if ((*it)->GetAsString(&switch_to_enable))
              command_line->AppendSwitch(switch_to_enable);
          }
        }
  
        // Disable client-side phishing detection in the renderer if it is
        // disabled in the Profile preferences or the browser process.
        if (!prefs->GetBoolean(prefs::kSafeBrowsingEnabled) ||
            !g_browser_process->safe_browsing_detection_service()) {
          command_line->AppendSwitch(
              switches::kDisableClientSidePhishingDetection);
        }
  
        if (prefs->GetBoolean(prefs::kPrintPreviewDisabled))
          command_line->AppendSwitch(switches::kDisablePrintPreview);
  
        InstantService* instant_service =
            InstantServiceFactory::GetForProfile(profile);
        if (instant_service &&
            instant_service->IsInstantProcess(process->GetID()))
          command_line->AppendSwitch(switches::kInstantProcess);
  
  #if !defined(OS_CHROMEOS)
        SigninClient* signin_client =
            ChromeSigninClientFactory::GetForProfile(profile);
        if (signin_client && signin_client->IsSigninProcess(process->GetID()))
          command_line->AppendSwitch(switches::kSigninProcess);
  #endif
      }
  
      if (IsAutoReloadEnabled())
        command_line->AppendSwitch(switches::kEnableOfflineAutoReload);
      if (IsAutoReloadVisibleOnlyEnabled()) {
        command_line->AppendSwitch(
            switches::kEnableOfflineAutoReloadVisibleOnly);
      }
  
      {
        // Enable load stale cache if this session is in the field trial or
        // the user explicitly enabled it.  Note that as far as the renderer
        // is concerned, the feature is enabled if-and-only-if the
        // kEnableOfflineLoadStaleCache flag is on the command line;
        // the yes/no/default behavior is only at the browser command line
        // level.
  
        // Command line switches override
        if (browser_command_line.HasSwitch(
                switches::kEnableOfflineLoadStaleCache)) {
          command_line->AppendSwitch(switches::kEnableOfflineLoadStaleCache);
        } else if (!browser_command_line.HasSwitch(
            switches::kDisableOfflineLoadStaleCache)) {
          std::string group =
              base::FieldTrialList::FindFullName("LoadStaleCacheExperiment");
  
          if (group == "Enabled")
            command_line->AppendSwitch(switches::kEnableOfflineLoadStaleCache);
        }
      }
  
      // Please keep this in alphabetical order.
      static const char* const kSwitchNames[] = {
        autofill::switches::kDisableFillOnAccountSelect,
        autofill::switches::kDisablePasswordGeneration,
        autofill::switches::kEnableFillOnAccountSelect,
        autofill::switches::kEnableFillOnAccountSelectNoHighlighting,
        autofill::switches::kEnablePasswordGeneration,
        autofill::switches::kEnablePasswordSaveOnInPageNavigation,
        autofill::switches::kEnableSingleClickAutofill,
        autofill::switches::kIgnoreAutocompleteOffForAutofill,
        autofill::switches::kLocalHeuristicsOnlyForPasswordGeneration,
        autofill::switches::kRespectAutocompleteOffForAutofill,
  #if defined(ENABLE_EXTENSIONS)
        extensions::switches::kAllowHTTPBackgroundPage,
        extensions::switches::kAllowLegacyExtensionManifests,
        extensions::switches::kEnableSurfaceWorker,
        extensions::switches::kEnableAppWindowControls,
        extensions::switches::kEnableEmbeddedExtensionOptions,
        extensions::switches::kEnableExperimentalExtensionApis,
        extensions::switches::kEnableScriptsRequireAction,
        extensions::switches::kExtensionsOnChromeURLs,
        extensions::switches::kWhitelistedExtensionID,
  #endif
        switches::kAppsCheckoutURL,
        switches::kAppsGalleryURL,
        switches::kCloudPrintURL,
        switches::kCloudPrintXmppEndpoint,
        switches::kDisableBundledPpapiFlash,
        switches::kDisableCastStreamingHWEncoding,
        switches::kDisableJavaScriptHarmonyShipping,
        switches::kDisableNewBookmarkApps,
        switches::kDisableOutOfProcessPdf,
        switches::kEnableBenchmarking,
        switches::kEnableNaCl,
  #if !defined(DISABLE_NACL)
        switches::kEnableNaClDebug,
        switches::kEnableNaClNonSfiMode,
  #endif
        switches::kEnableNetBenchmarking,
        switches::kEnableOutOfProcessPdf,
        switches::kEnablePluginPlaceholderShadowDom,
        switches::kEnableShowModalDialog,
        switches::kEnableWebBasedSignin,
        switches::kJavaScriptHarmony,
        switches::kMessageLoopHistogrammer,
        switches::kPlaybackMode,
        switches::kPpapiFlashArgs,
        switches::kPpapiFlashPath,
        switches::kPpapiFlashVersion,
        switches::kProfilingAtStart,
        switches::kProfilingFile,
        switches::kProfilingFlush,
        switches::kRecordMode,
        translate::switches::kTranslateSecurityOrigin,
      };
  
      command_line->CopySwitchesFrom(browser_command_line, kSwitchNames,
                                     arraysize(kSwitchNames));
    } else if (process_type == switches::kUtilityProcess) {
  #if defined(ENABLE_EXTENSIONS)
      static const char* const kSwitchNames[] = {
        extensions::switches::kAllowHTTPBackgroundPage,
        extensions::switches::kEnableExperimentalExtensionApis,
        extensions::switches::kExtensionsOnChromeURLs,
        extensions::switches::kWhitelistedExtensionID,
      };
  
      command_line->CopySwitchesFrom(browser_command_line, kSwitchNames,
                                     arraysize(kSwitchNames));
  #endif
    } else if (process_type == switches::kPluginProcess) {
  #if defined(OS_CHROMEOS)
      static const char* const kSwitchNames[] = {
        chromeos::switches::kLoginProfile,
      };
  
      command_line->CopySwitchesFrom(browser_command_line, kSwitchNames,
                                     arraysize(kSwitchNames));
  #endif
    } else if (process_type == switches::kZygoteProcess) {
      static const char* const kSwitchNames[] = {
        // Load (in-process) Pepper plugins in-process in the zygote pre-sandbox.
        switches::kDisableBundledPpapiFlash,
  #if !defined(DISABLE_NACL)
        switches::kEnableNaClDebug,
        switches::kEnableNaClNonSfiMode,
        switches::kNaClDangerousNoSandboxNonSfi,
        switches::kUseNaClHelperNonSfi,
  #endif
        switches::kPpapiFlashPath,
        switches::kPpapiFlashVersion,
      };
  
      command_line->CopySwitchesFrom(browser_command_line, kSwitchNames,
                                     arraysize(kSwitchNames));
    } else if (process_type == switches::kGpuProcess) {
      // If --ignore-gpu-blacklist is passed in, don't send in crash reports
      // because GPU is expected to be unreliable.
      if (browser_command_line.HasSwitch(switches::kIgnoreGpuBlacklist) &&
          !command_line->HasSwitch(switches::kDisableBreakpad))
        command_line->AppendSwitch(switches::kDisableBreakpad);
    }
  
    // The command line switch kEnableBenchmarking needs to be specified along
    // with the kEnableStatsTable switch to ensure that the stats table global
    // is initialized correctly.
    if (command_line->HasSwitch(switches::kEnableBenchmarking))
      DCHECK(command_line->HasSwitch(switches::kEnableStatsTable));
  }
  
  std::string ChromeContentBrowserClient::GetApplicationLocale() {
    if (BrowserThread::CurrentlyOn(BrowserThread::IO))
      return g_io_thread_application_locale.Get();
    return g_browser_process->GetApplicationLocale();
  }
  
  std::string ChromeContentBrowserClient::GetAcceptLangs(
      content::BrowserContext* context) {
    Profile* profile = Profile::FromBrowserContext(context);
    return profile->GetPrefs()->GetString(prefs::kAcceptLanguages);
  }
  
  const gfx::ImageSkia* ChromeContentBrowserClient::GetDefaultFavicon() {
    ResourceBundle& rb = ResourceBundle::GetSharedInstance();
    return rb.GetNativeImageNamed(IDR_DEFAULT_FAVICON).ToImageSkia();
  }
  
  bool ChromeContentBrowserClient::AllowAppCache(
      const GURL& manifest_url,
      const GURL& first_party,
      content::ResourceContext* context) {
    DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
    ProfileIOData* io_data = ProfileIOData::FromResourceContext(context);
    return io_data->GetCookieSettings()->
        IsSettingCookieAllowed(manifest_url, first_party);
  }
  
  bool ChromeContentBrowserClient::AllowServiceWorker(
      const GURL& scope,
      const GURL& first_party_url,
      content::ResourceContext* context) {
    DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
    ProfileIOData* io_data = ProfileIOData::FromResourceContext(context);
    return io_data->GetCookieSettings()->
        IsSettingCookieAllowed(scope, first_party_url);
  }
  
  bool ChromeContentBrowserClient::AllowGetCookie(
      const GURL& url,
      const GURL& first_party,
      const net::CookieList& cookie_list,
      content::ResourceContext* context,
      int render_process_id,
      int render_frame_id) {
    DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
    ProfileIOData* io_data = ProfileIOData::FromResourceContext(context);
    bool allow = io_data->GetCookieSettings()->
        IsReadingCookieAllowed(url, first_party);
  
    BrowserThread::PostTask(
        BrowserThread::UI, FROM_HERE,
        base::Bind(&TabSpecificContentSettings::CookiesRead, render_process_id,
                   render_frame_id, url, first_party, cookie_list, !allow, true));
    return allow;
  }
  
  bool ChromeContentBrowserClient::AllowSetCookie(
      const GURL& url,
      const GURL& first_party,
      const std::string& cookie_line,
      content::ResourceContext* context,
      int render_process_id,
      int render_frame_id,
      net::CookieOptions* options) {
    DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
    ProfileIOData* io_data = ProfileIOData::FromResourceContext(context);
    CookieSettings* cookie_settings = io_data->GetCookieSettings();
    bool allow = cookie_settings->IsSettingCookieAllowed(url, first_party);
  
    if (prerender_tracker_) {
      prerender_tracker_->OnCookieChangedForURL(
          render_process_id,
          context->GetRequestContext()->cookie_store()->GetCookieMonster(),
          url);
    }
  
    BrowserThread::PostTask(
        BrowserThread::UI, FROM_HERE,
        base::Bind(&TabSpecificContentSettings::CookieChanged, render_process_id,
                   render_frame_id, url, first_party, cookie_line, *options,
                   !allow));
    return allow;
  }
  
  bool ChromeContentBrowserClient::AllowSaveLocalState(
      content::ResourceContext* context) {
    DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
    ProfileIOData* io_data = ProfileIOData::FromResourceContext(context);
    CookieSettings* cookie_settings = io_data->GetCookieSettings();
    ContentSetting setting = cookie_settings->GetDefaultCookieSetting(NULL);
  
    // TODO(bauerb): Should we also disallow local state if the default is BLOCK?
    // Could we even support per-origin settings?
    return setting != CONTENT_SETTING_SESSION_ONLY;
  }
  
  bool ChromeContentBrowserClient::AllowWorkerDatabase(
      const GURL& url,
      const base::string16& name,
      const base::string16& display_name,
      unsigned long estimated_size,
      content::ResourceContext* context,
      const std::vector<std::pair<int, int> >& render_frames) {
    DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
    ProfileIOData* io_data = ProfileIOData::FromResourceContext(context);
    CookieSettings* cookie_settings = io_data->GetCookieSettings();
    bool allow = cookie_settings->IsSettingCookieAllowed(url, url);
  
    // Record access to database for potential display in UI.
    std::vector<std::pair<int, int> >::const_iterator i;
    for (i = render_frames.begin(); i != render_frames.end(); ++i) {
      BrowserThread::PostTask(
          BrowserThread::UI, FROM_HERE,
          base::Bind(&TabSpecificContentSettings::WebDatabaseAccessed,
                     i->first, i->second, url, name, display_name, !allow));
    }
  
    return allow;
  }
  
  void ChromeContentBrowserClient::AllowWorkerFileSystem(
      const GURL& url,
      content::ResourceContext* context,
      const std::vector<std::pair<int, int> >& render_frames,
      base::Callback<void(bool)> callback) {
    DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
    ProfileIOData* io_data = ProfileIOData::FromResourceContext(context);
    CookieSettings* cookie_settings = io_data->GetCookieSettings();
    bool allow = cookie_settings->IsSettingCookieAllowed(url, url);
  
  #if defined(ENABLE_EXTENSIONS)
    GuestPermissionRequestHelper(url, render_frames, callback, allow);
  #else
    FileSystemAccessed(url, render_frames, callback, allow);
  #endif
  }
  
  #if defined(ENABLE_EXTENSIONS)
  void ChromeContentBrowserClient::GuestPermissionRequestHelper(
      const GURL& url,
      const std::vector<std::pair<int, int> >& render_frames,
      base::Callback<void(bool)> callback,
      bool allow) {
    DCHECK(BrowserThread:: CurrentlyOn(BrowserThread::IO));
    std::vector<std::pair<int, int> >::const_iterator i;
    std::map<int, int> process_map;
    std::map<int, int>::const_iterator it;
    bool has_web_view_guest = false;
    // Record access to file system for potential display in UI.
    for (i = render_frames.begin(); i != render_frames.end(); ++i) {
      if (process_map.find(i->first) != process_map.end())
        continue;
  
      process_map.insert(std::pair<int, int>(i->first, i->second));
  
      if (extensions::WebViewRendererState::GetInstance()->IsGuest(i->first))
        has_web_view_guest = true;
    }
    if (!has_web_view_guest) {
      FileSystemAccessed(url, render_frames, callback, allow);
      return;
    }
    DCHECK_EQ(1U, process_map.size());
    it = process_map.begin();
    BrowserThread::PostTask(
        BrowserThread::UI,
        FROM_HERE,
        base::Bind(&ChromeContentBrowserClient::
                    RequestFileSystemPermissionOnUIThread,
                    it->first,
                    it->second,
                    url,
                    allow,
                    base::Bind(&ChromeContentBrowserClient::FileSystemAccessed,
                              weak_factory_.GetWeakPtr(),
                              url,
                              render_frames,
                              callback)));
  }
  
  void ChromeContentBrowserClient::RequestFileSystemPermissionOnUIThread(
      int render_process_id,
      int render_frame_id,
      const GURL& url,
      bool allowed_by_default,
      const base::Callback<void(bool)>& callback) {
    DCHECK(BrowserThread:: CurrentlyOn(BrowserThread::UI));
    extensions::WebViewPermissionHelper* web_view_permission_helper =
        extensions::WebViewPermissionHelper::FromFrameID(
            render_process_id, render_frame_id);
    web_view_permission_helper->RequestFileSystemPermission(url,
                                                            allowed_by_default,
                                                            callback);
  }
  #endif
  
  void ChromeContentBrowserClient::FileSystemAccessed(
      const GURL& url,
      const std::vector<std::pair<int, int> >& render_frames,
      base::Callback<void(bool)> callback,
      bool allow) {
    // Record access to file system for potential display in UI.
    std::vector<std::pair<int, int> >::const_iterator i;
    for (i = render_frames.begin(); i != render_frames.end(); ++i) {
      BrowserThread::PostTask(
          BrowserThread::UI,
          FROM_HERE,
          base::Bind(&TabSpecificContentSettings::FileSystemAccessed,
                     i->first, i->second, url, !allow));
    }
    callback.Run(allow);
  }
  
  bool ChromeContentBrowserClient::AllowWorkerIndexedDB(
      const GURL& url,
      const base::string16& name,
      content::ResourceContext* context,
      const std::vector<std::pair<int, int> >& render_frames) {
    DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
    ProfileIOData* io_data = ProfileIOData::FromResourceContext(context);
    CookieSettings* cookie_settings = io_data->GetCookieSettings();
    bool allow = cookie_settings->IsSettingCookieAllowed(url, url);
  
    // Record access to IndexedDB for potential display in UI.
    std::vector<std::pair<int, int> >::const_iterator i;
    for (i = render_frames.begin(); i != render_frames.end(); ++i) {
      BrowserThread::PostTask(
          BrowserThread::UI, FROM_HERE,
          base::Bind(&TabSpecificContentSettings::IndexedDBAccessed,
                     i->first, i->second, url, name, !allow));
    }
  
    return allow;
  }
  
  net::URLRequestContext*
  ChromeContentBrowserClient::OverrideRequestContextForURL(
      const GURL& url, content::ResourceContext* context) {
    DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
  #if defined(ENABLE_EXTENSIONS)
    if (url.SchemeIs(extensions::kExtensionScheme)) {
      ProfileIOData* io_data = ProfileIOData::FromResourceContext(context);
      return io_data->extensions_request_context();
    }
  #endif
  
    return NULL;
  }
  
  QuotaPermissionContext*
  ChromeContentBrowserClient::CreateQuotaPermissionContext() {
    return new ChromeQuotaPermissionContext();
  }
  
  void ChromeContentBrowserClient::AllowCertificateError(
      int render_process_id,
      int render_frame_id,
      int cert_error,
      const net::SSLInfo& ssl_info,
      const GURL& request_url,
      ResourceType resource_type,
      bool overridable,
      bool strict_enforcement,
      bool expired_previous_decision,
      const base::Callback<void(bool)>& callback,
      content::CertificateRequestResultType* result) {
    if (resource_type != content::RESOURCE_TYPE_MAIN_FRAME) {
      // A sub-resource has a certificate error.  The user doesn't really
      // have a context for making the right decision, so block the
      // request hard, without an info bar to allow showing the insecure
      // content.
      *result = content::CERTIFICATE_REQUEST_RESULT_TYPE_DENY;
      return;
    }
  
    // If the tab is being prerendered, cancel the prerender and the request.
    content::RenderFrameHost* render_frame_host =
        content::RenderFrameHost::FromID(render_process_id, render_frame_id);
    WebContents* tab = WebContents::FromRenderFrameHost(render_frame_host);
    if (!tab) {
      NOTREACHED();
      return;
    }
  
    prerender::PrerenderContents* prerender_contents =
        prerender::PrerenderContents::FromWebContents(tab);
    if (prerender_contents) {
      prerender_contents->Destroy(prerender::FINAL_STATUS_SSL_ERROR);
      *result = content::CERTIFICATE_REQUEST_RESULT_TYPE_CANCEL;
      return;
    }
  
    // Otherwise, display an SSL blocking page. The interstitial page takes
    // ownership of ssl_blocking_page.
    int options_mask = 0;
    if (overridable)
      options_mask |= SSLBlockingPage::OVERRIDABLE;
    if (strict_enforcement)
      options_mask |= SSLBlockingPage::STRICT_ENFORCEMENT;
    if (expired_previous_decision)
      options_mask |= SSLBlockingPage::EXPIRED_BUT_PREVIOUSLY_ALLOWED;
  
    SSLErrorHandler::HandleSSLError(
        tab, cert_error, ssl_info, request_url, options_mask, callback);
  }
  
  void ChromeContentBrowserClient::SelectClientCertificate(
      int render_process_id,
      int render_frame_id,
      net::SSLCertRequestInfo* cert_request_info,
      const base::Callback<void(net::X509Certificate*)>& callback) {
    content::RenderFrameHost* rfh = content::RenderFrameHost::FromID(
        render_process_id, render_frame_id);
    WebContents* tab = WebContents::FromRenderFrameHost(rfh);
    if (!tab) {
      // TODO(davidben): This makes the request hang, but returning no certificate
      // also breaks. It should abort the request. See https://crbug.com/417092
      return;
    }
  
    prerender::PrerenderContents* prerender_contents =
        prerender::PrerenderContents::FromWebContents(tab);
    if (prerender_contents) {
      prerender_contents->Destroy(
          prerender::FINAL_STATUS_SSL_CLIENT_CERTIFICATE_REQUESTED);
      return;
    }
  
    GURL requesting_url("https://" + cert_request_info->host_and_port.ToString());
    DCHECK(requesting_url.is_valid())
        << "Invalid URL string: https://"
        << cert_request_info->host_and_port.ToString();
  
    Profile* profile = Profile::FromBrowserContext(tab->GetBrowserContext());
    scoped_ptr<base::Value> filter =
        profile->GetHostContentSettingsMap()->GetWebsiteSetting(
            requesting_url,
            requesting_url,
            CONTENT_SETTINGS_TYPE_AUTO_SELECT_CERTIFICATE,
            std::string(),
            NULL);
  
    if (filter.get()) {
      // Try to automatically select a client certificate.
      if (filter->IsType(base::Value::TYPE_DICTIONARY)) {
        base::DictionaryValue* filter_dict =
            static_cast<base::DictionaryValue*>(filter.get());
  
        const std::vector<scoped_refptr<net::X509Certificate> >&
            all_client_certs = cert_request_info->client_certs;
        for (size_t i = 0; i < all_client_certs.size(); ++i) {
          if (CertMatchesFilter(*all_client_certs[i].get(), *filter_dict)) {
            // Use the first certificate that is matched by the filter.
            callback.Run(all_client_certs[i].get());
            return;
          }
        }
      } else {
        NOTREACHED();
      }
    }
  
    chrome::ShowSSLClientCertificateSelector(tab, cert_request_info, callback);
  }
  
  void ChromeContentBrowserClient::AddCertificate(
      net::CertificateMimeType cert_type,
      const void* cert_data,
      size_t cert_size,
      int render_process_id,
      int render_frame_id) {
    chrome::SSLAddCertificate(cert_type, cert_data, cert_size,
                              render_process_id, render_frame_id);
  }
  
  content::MediaObserver* ChromeContentBrowserClient::GetMediaObserver() {
    return MediaCaptureDevicesDispatcher::GetInstance();
  }
  
  content::PlatformNotificationService*
  ChromeContentBrowserClient::GetPlatformNotificationService() {
  #if defined(ENABLE_NOTIFICATIONS)
    return PlatformNotificationServiceImpl::GetInstance();
  #else
    NOTIMPLEMENTED();
    return NULL;
  #endif
  }
  
  void ChromeContentBrowserClient::RequestPermission(
      content::PermissionType permission,
      content::WebContents* web_contents,
      int bridge_id,
      const GURL& requesting_frame,
      bool user_gesture,
      const base::Callback<void(bool)>& result_callback) {
    int render_process_id = web_contents->GetRenderProcessHost()->GetID();
    int render_view_id = web_contents->GetRenderViewHost()->GetRoutingID();
    Profile* profile =
        Profile::FromBrowserContext(web_contents->GetBrowserContext());
  
    const PermissionRequestID request_id(render_process_id,
                                         render_view_id,
                                         bridge_id,
                                         requesting_frame);
  
    switch (permission) {
      case content::PERMISSION_MIDI_SYSEX:
        MidiPermissionContextFactory::GetForProfile(profile)
            ->RequestPermission(web_contents,
                                request_id,
                                requesting_frame,
                                user_gesture,
                                result_callback);
        break;
      case content::PERMISSION_NOTIFICATIONS:
  #if defined(ENABLE_NOTIFICATIONS)
        DesktopNotificationServiceFactory::GetForProfile(profile)
            ->RequestNotificationPermission(web_contents,
                                            request_id,
                                            requesting_frame,
                                            user_gesture,
                                            result_callback);
  #else
        NOTIMPLEMENTED();
  #endif
        break;
      case content::PERMISSION_GEOLOCATION:
        GeolocationPermissionContextFactory::GetForProfile(profile)
            ->RequestPermission(web_contents,
                                request_id,
                                requesting_frame.GetOrigin(),
                                user_gesture,
                                result_callback);
        break;
      case content::PERMISSION_PROTECTED_MEDIA:
  #if defined(OS_ANDROID)
        ProtectedMediaIdentifierPermissionContextFactory::GetForProfile(profile)
            ->RequestPermission(web_contents,
                                request_id,
                                requesting_frame.GetOrigin(),
                                user_gesture,
                                result_callback);
  #else
        NOTIMPLEMENTED();
  #endif
        break;
      case content::PERMISSION_PUSH_MESSAGING:
        gcm::PushMessagingPermissionContextFactory::GetForProfile(profile)
            ->RequestPermission(web_contents,
                                request_id,
                                requesting_frame.GetOrigin(),
                                user_gesture,
                                result_callback);
        break;
      case content::PERMISSION_NUM:
        NOTREACHED() << "Invalid RequestPermission for " << permission;
        break;
    }
  }
  
  content::PermissionStatus ChromeContentBrowserClient::GetPermissionStatus(
      content::PermissionType permission,
      content::BrowserContext* browser_context,
      const GURL& requesting_origin,
      const GURL& embedding_origin) {
    DCHECK(browser_context);
    Profile* profile = Profile::FromBrowserContext(browser_context);
  
    PermissionContextBase* context = nullptr;
    switch (permission) {
      case content::PERMISSION_MIDI_SYSEX:
        context = MidiPermissionContextFactory::GetForProfile(profile);
        break;
      case content::PERMISSION_NOTIFICATIONS:
  #if defined(ENABLE_NOTIFICATIONS)
        context = DesktopNotificationServiceFactory::GetForProfile(profile);
  #else
        NOTIMPLEMENTED();
  #endif
        break;
      case content::PERMISSION_GEOLOCATION:
        context = GeolocationPermissionContextFactory::GetForProfile(profile);
        break;
      case content::PERMISSION_PROTECTED_MEDIA:
        NOTIMPLEMENTED();
        break;
      case content::PERMISSION_PUSH_MESSAGING:
        context = gcm::PushMessagingPermissionContextFactory::GetForProfile(
            profile);
        break;
      case content::PERMISSION_NUM:
        NOTREACHED() << "Invalid RequestPermission for " << permission;
        break;
    }
  
    ContentSetting result = context
        ? context->GetPermissionStatus(requesting_origin.GetOrigin(),
                                       embedding_origin.GetOrigin())
        : CONTENT_SETTING_DEFAULT;
  
    return ContentSettingToPermissionStatus(result);
  }
  
  void ChromeContentBrowserClient::CancelPermissionRequest(
      content::PermissionType permission,
      content::WebContents* web_contents,
      int bridge_id,
      const GURL& requesting_frame) {
    int render_process_id = web_contents->GetRenderProcessHost()->GetID();
    int render_view_id = web_contents->GetRenderViewHost()->GetRoutingID();
  
    const PermissionRequestID request_id(render_process_id,
                                         render_view_id,
                                         bridge_id,
                                         requesting_frame);
    Profile* profile =
        Profile::FromBrowserContext(web_contents->GetBrowserContext());
    switch (permission) {
      case content::PERMISSION_MIDI_SYSEX:
        MidiPermissionContextFactory::GetForProfile(profile)
            ->CancelPermissionRequest(web_contents, request_id);
        break;
      case content::PERMISSION_NOTIFICATIONS:
  #if defined(ENABLE_NOTIFICATIONS)
        DesktopNotificationServiceFactory::GetForProfile(profile)
            ->CancelPermissionRequest(web_contents, request_id);
  #else
        NOTIMPLEMENTED();
  #endif
        break;
      case content::PERMISSION_GEOLOCATION:
        GeolocationPermissionContextFactory::GetForProfile(profile)
            ->CancelPermissionRequest(web_contents, request_id);
        break;
      case content::PERMISSION_PROTECTED_MEDIA:
  #if defined(OS_ANDROID)
        ProtectedMediaIdentifierPermissionContextFactory::GetForProfile(profile)
            ->CancelPermissionRequest(web_contents, request_id);
  #else
        NOTIMPLEMENTED();
  #endif
        break;
      case content::PERMISSION_PUSH_MESSAGING:
        NOTIMPLEMENTED() << "CancelPermission not implemented for " << permission;
        break;
      case content::PERMISSION_NUM:
        NOTREACHED() << "Invalid CancelPermission for " << permission;
        break;
    }
  }
  
  // Helper method to translate from Permissions to ContentSettings
  static ContentSettingsType PermissionToContentSetting(
      content::PermissionType permission) {
    switch (permission) {
      case content::PERMISSION_MIDI_SYSEX:
        return CONTENT_SETTINGS_TYPE_MIDI_SYSEX;
      case content::PERMISSION_PUSH_MESSAGING:
        return CONTENT_SETTINGS_TYPE_PUSH_MESSAGING;
      case content::PERMISSION_NOTIFICATIONS:
        return CONTENT_SETTINGS_TYPE_NOTIFICATIONS;
      case content::PERMISSION_GEOLOCATION:
        return CONTENT_SETTINGS_TYPE_GEOLOCATION;
  #if defined(OS_ANDROID) || defined(OS_CHROMEOS)
      case content::PERMISSION_PROTECTED_MEDIA:
        return CONTENT_SETTINGS_TYPE_PROTECTED_MEDIA_IDENTIFIER;
  #endif
      default:
        NOTREACHED() << "Unknown content setting for permission " << permission;
        return CONTENT_SETTINGS_TYPE_DEFAULT;
    }
  }
  
  void ChromeContentBrowserClient::RegisterPermissionUsage(
      content::PermissionType permission,
      content::WebContents* web_contents,
      const GURL& frame_url,
      const GURL& main_frame_url) {
    Profile::FromBrowserContext(web_contents->GetBrowserContext())
        ->GetHostContentSettingsMap()
        ->UpdateLastUsage(
            frame_url, main_frame_url, PermissionToContentSetting(permission));
  }
  
  bool ChromeContentBrowserClient::CanCreateWindow(
      const GURL& opener_url,
      const GURL& opener_top_level_frame_url,
      const GURL& source_origin,
      WindowContainerType container_type,
      const GURL& target_url,
      const content::Referrer& referrer,
      WindowOpenDisposition disposition,
      const WebWindowFeatures& features,
      bool user_gesture,
      bool opener_suppressed,
      content::ResourceContext* context,
      int render_process_id,
      int opener_id,
      bool* no_javascript_access) {
    DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
  
    *no_javascript_access = false;
  
    // If the opener is trying to create a background window but doesn't have
    // the appropriate permission, fail the attempt.
    if (container_type == WINDOW_CONTAINER_TYPE_BACKGROUND) {
  #if defined(ENABLE_EXTENSIONS)
      ProfileIOData* io_data = ProfileIOData::FromResourceContext(context);
      InfoMap* map = io_data->GetExtensionInfoMap();
      if (!map->SecurityOriginHasAPIPermission(
              source_origin,
              render_process_id,
              APIPermission::kBackground)) {
        return false;
      }
  
      // Note: this use of GetExtensionOrAppByURL is safe but imperfect.  It may
      // return a recently installed Extension even if this CanCreateWindow call
      // was made by an old copy of the page in a normal web process.  That's ok,
      // because the permission check above would have caused an early return
      // already. We must use the full URL to find hosted apps, though, and not
      // just the origin.
      const Extension* extension =
          map->extensions().GetExtensionOrAppByURL(opener_url);
      if (extension && !extensions::BackgroundInfo::AllowJSAccess(extension))
        *no_javascript_access = true;
  #endif
  
      return true;
    }
  
  #if defined(ENABLE_EXTENSIONS)
    if (extensions::WebViewRendererState::GetInstance()->IsGuest(
        render_process_id))
      return true;
  #endif
  
    HostContentSettingsMap* content_settings =
        ProfileIOData::FromResourceContext(context)->GetHostContentSettingsMap();
    BlockedWindowParams blocked_params(target_url,
                                       referrer,
                                       disposition,
                                       features,
                                       user_gesture,
                                       opener_suppressed,
                                       render_process_id,
                                       opener_id);
  
    if (!user_gesture &&
        !base::CommandLine::ForCurrentProcess()->HasSwitch(
            switches::kDisablePopupBlocking)) {
      if (content_settings->GetContentSetting(opener_top_level_frame_url,
                                              opener_top_level_frame_url,
                                              CONTENT_SETTINGS_TYPE_POPUPS,
                                              std::string()) !=
          CONTENT_SETTING_ALLOW) {
        BrowserThread::PostTask(BrowserThread::UI,
                                FROM_HERE,
                                base::Bind(&HandleBlockedPopupOnUIThread,
                                           blocked_params));
        return false;
      }
    }
  
  #if defined(OS_ANDROID)
    if (SingleTabModeTabHelper::IsRegistered(render_process_id, opener_id)) {
      BrowserThread::PostTask(BrowserThread::UI,
                              FROM_HERE,
                              base::Bind(&HandleSingleTabModeBlockOnUIThread,
                                         blocked_params));
      return false;
    }
  #endif
  
    return true;
  }
  
  void ChromeContentBrowserClient::ResourceDispatcherHostCreated() {
    DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
    prerender_tracker_ = g_browser_process->prerender_tracker();
    return g_browser_process->ResourceDispatcherHostCreated();
  }
  
  content::SpeechRecognitionManagerDelegate*
      ChromeContentBrowserClient::CreateSpeechRecognitionManagerDelegate() {
    return new speech::ChromeSpeechRecognitionManagerDelegate();
  }
  
  net::NetLog* ChromeContentBrowserClient::GetNetLog() {
    return g_browser_process->net_log();
  }
  
  AccessTokenStore* ChromeContentBrowserClient::CreateAccessTokenStore() {
    return new ChromeAccessTokenStore();
  }
  
  bool ChromeContentBrowserClient::IsFastShutdownPossible() {
    return true;
  }
  
  void ChromeContentBrowserClient::OverrideWebkitPrefs(
      RenderViewHost* rvh, const GURL& url, WebPreferences* web_prefs) {
    Profile* profile = Profile::FromBrowserContext(
        rvh->GetProcess()->GetBrowserContext());
    PrefService* prefs = profile->GetPrefs();
  
    // Fill per-script font preferences. These are not registered on Android
    // - http://crbug.com/308033.
  #if !defined(OS_ANDROID)
    FontFamilyCache::FillFontFamilyMap(profile,
                                       prefs::kWebKitStandardFontFamilyMap,
                                       &web_prefs->standard_font_family_map);
    FontFamilyCache::FillFontFamilyMap(profile,
                                       prefs::kWebKitFixedFontFamilyMap,
                                       &web_prefs->fixed_font_family_map);
    FontFamilyCache::FillFontFamilyMap(profile,
                                       prefs::kWebKitSerifFontFamilyMap,
                                       &web_prefs->serif_font_family_map);
    FontFamilyCache::FillFontFamilyMap(profile,
                                       prefs::kWebKitSansSerifFontFamilyMap,
                                       &web_prefs->sans_serif_font_family_map);
    FontFamilyCache::FillFontFamilyMap(profile,
                                       prefs::kWebKitCursiveFontFamilyMap,
                                       &web_prefs->cursive_font_family_map);
    FontFamilyCache::FillFontFamilyMap(profile,
                                       prefs::kWebKitFantasyFontFamilyMap,
                                       &web_prefs->fantasy_font_family_map);
    FontFamilyCache::FillFontFamilyMap(profile,
                                       prefs::kWebKitPictographFontFamilyMap,
                                       &web_prefs->pictograph_font_family_map);
  #endif
  
    web_prefs->default_font_size =
        prefs->GetInteger(prefs::kWebKitDefaultFontSize);
    web_prefs->default_fixed_font_size =
        prefs->GetInteger(prefs::kWebKitDefaultFixedFontSize);
    web_prefs->minimum_font_size =
        prefs->GetInteger(prefs::kWebKitMinimumFontSize);
    web_prefs->minimum_logical_font_size =
        prefs->GetInteger(prefs::kWebKitMinimumLogicalFontSize);
  
    web_prefs->default_encoding = prefs->GetString(prefs::kDefaultCharset);
  
    web_prefs->javascript_can_open_windows_automatically =
        prefs->GetBoolean(prefs::kWebKitJavascriptCanOpenWindowsAutomatically);
    web_prefs->dom_paste_enabled =
        prefs->GetBoolean(prefs::kWebKitDomPasteEnabled);
    web_prefs->shrinks_standalone_images_to_fit =
        prefs->GetBoolean(prefs::kWebKitShrinksStandaloneImagesToFit);
    web_prefs->tabs_to_links = prefs->GetBoolean(prefs::kWebkitTabsToLinks);
  
    if (!prefs->GetBoolean(prefs::kWebKitJavascriptEnabled))
      web_prefs->javascript_enabled = false;
    if (!prefs->GetBoolean(prefs::kWebKitWebSecurityEnabled))
      web_prefs->web_security_enabled = false;
    if (!prefs->GetBoolean(prefs::kWebKitPluginsEnabled))
      web_prefs->plugins_enabled = false;
    if (!prefs->GetBoolean(prefs::kWebKitJavaEnabled))
      web_prefs->java_enabled = false;
    web_prefs->loads_images_automatically =
        prefs->GetBoolean(prefs::kWebKitLoadsImagesAutomatically);
  
    if (prefs->GetBoolean(prefs::kDisable3DAPIs))
      web_prefs->experimental_webgl_enabled = false;
  
    web_prefs->allow_displaying_insecure_content =
        prefs->GetBoolean(prefs::kWebKitAllowDisplayingInsecureContent);
    web_prefs->allow_running_insecure_content =
        prefs->GetBoolean(prefs::kWebKitAllowRunningInsecureContent);
  #if defined(OS_ANDROID)
    web_prefs->font_scale_factor =
        static_cast<float>(prefs->GetDouble(prefs::kWebKitFontScaleFactor));
    web_prefs->device_scale_adjustment = GetDeviceScaleAdjustment();
    web_prefs->force_enable_zoom =
        prefs->GetBoolean(prefs::kWebKitForceEnableZoom);
  #endif
  
  #if defined(OS_ANDROID)
    web_prefs->password_echo_enabled =
        prefs->GetBoolean(prefs::kWebKitPasswordEchoEnabled);
  #else
    web_prefs->password_echo_enabled = browser_defaults::kPasswordEchoEnabled;
  #endif
  
    web_prefs->asynchronous_spell_checking_enabled = true;
    web_prefs->unified_textchecker_enabled = true;
  
    web_prefs->uses_universal_detector =
        prefs->GetBoolean(prefs::kWebKitUsesUniversalDetector);
    web_prefs->text_areas_are_resizable =
        prefs->GetBoolean(prefs::kWebKitTextAreasAreResizable);
    web_prefs->hyperlink_auditing_enabled =
        prefs->GetBoolean(prefs::kEnableHyperlinkAuditing);
  
    // Make sure we will set the default_encoding with canonical encoding name.
    web_prefs->default_encoding =
        CharacterEncoding::GetCanonicalEncodingNameByAliasName(
            web_prefs->default_encoding);
    if (web_prefs->default_encoding.empty()) {
      prefs->ClearPref(prefs::kDefaultCharset);
      web_prefs->default_encoding = prefs->GetString(prefs::kDefaultCharset);
    }
    DCHECK(!web_prefs->default_encoding.empty());
  
    if (base::CommandLine::ForCurrentProcess()->HasSwitch(
            switches::kEnablePotentiallyAnnoyingSecurityFeatures)) {
      web_prefs->strict_mixed_content_checking = true;
      web_prefs->strict_powerful_feature_restrictions = true;
    }
  
    for (size_t i = 0; i < extra_parts_.size(); ++i)
      extra_parts_[i]->OverrideWebkitPrefs(rvh, url, web_prefs);
  }
  
  void ChromeContentBrowserClient::BrowserURLHandlerCreated(
      BrowserURLHandler* handler) {
    for (size_t i = 0; i < extra_parts_.size(); ++i)
      extra_parts_[i]->BrowserURLHandlerCreated(handler);
  
    // about: handler. Must come before chrome: handler, since it will
    // rewrite about: urls to chrome: URLs and then expect chrome: to
    // actually handle them.
    handler->AddHandlerPair(&WillHandleBrowserAboutURL,
                            BrowserURLHandler::null_handler());
  
  #if defined(OS_ANDROID)
    // Handler to rewrite chrome://newtab on Android.
    handler->AddHandlerPair(&chrome::android::HandleAndroidNewTabURL,
                            BrowserURLHandler::null_handler());
  #else
    // Handler to rewrite chrome://newtab for InstantExtended.
    handler->AddHandlerPair(&chrome::HandleNewTabURLRewrite,
                            &chrome::HandleNewTabURLReverseRewrite);
  #endif
  
    // chrome: & friends.
    handler->AddHandlerPair(&HandleWebUI, &HandleWebUIReverse);
  }
  
  void ChromeContentBrowserClient::ClearCache(RenderViewHost* rvh) {
    Profile* profile = Profile::FromBrowserContext(
        rvh->GetSiteInstance()->GetProcess()->GetBrowserContext());
    BrowsingDataRemover* remover =
        BrowsingDataRemover::CreateForUnboundedRange(profile);
    remover->Remove(BrowsingDataRemover::REMOVE_CACHE,
                    BrowsingDataHelper::UNPROTECTED_WEB);
    // BrowsingDataRemover takes care of deleting itself when done.
  }
  
  void ChromeContentBrowserClient::ClearCookies(RenderViewHost* rvh) {
    Profile* profile = Profile::FromBrowserContext(
        rvh->GetSiteInstance()->GetProcess()->GetBrowserContext());
    BrowsingDataRemover* remover =
        BrowsingDataRemover::CreateForUnboundedRange(profile);
    int remove_mask = BrowsingDataRemover::REMOVE_SITE_DATA;
    remover->Remove(remove_mask, BrowsingDataHelper::UNPROTECTED_WEB);
    // BrowsingDataRemover takes care of deleting itself when done.
  }
  
  base::FilePath ChromeContentBrowserClient::GetDefaultDownloadDirectory() {
    return DownloadPrefs::GetDefaultDownloadDirectory();
  }
  
  std::string ChromeContentBrowserClient::GetDefaultDownloadName() {
    return l10n_util::GetStringUTF8(IDS_DEFAULT_DOWNLOAD_FILENAME);
  }
  
  void ChromeContentBrowserClient::DidCreatePpapiPlugin(
      content::BrowserPpapiHost* browser_host) {
  #if defined(ENABLE_PLUGINS)
    ChromeContentBrowserClientPluginsPart::DidCreatePpapiPlugin(browser_host);
  #endif
  }
  
  content::BrowserPpapiHost*
      ChromeContentBrowserClient::GetExternalBrowserPpapiHost(
          int plugin_process_id) {
  #if !defined(DISABLE_NACL)
    content::BrowserChildProcessHostIterator iter(PROCESS_TYPE_NACL_LOADER);
    while (!iter.Done()) {
      nacl::NaClProcessHost* host = static_cast<nacl::NaClProcessHost*>(
          iter.GetDelegate());
      if (host->process() &&
          host->process()->GetData().id == plugin_process_id) {
        // Found the plugin.
        return host->browser_ppapi_host();
      }
      ++iter;
    }
  #endif
    return NULL;
  }
  
  bool ChromeContentBrowserClient::AllowPepperSocketAPI(
      content::BrowserContext* browser_context,
      const GURL& url,
      bool private_api,
      const content::SocketPermissionRequest* params) {
  #if defined(ENABLE_PLUGINS) && defined(ENABLE_EXTENSIONS)
    return ChromeContentBrowserClientPluginsPart::AllowPepperSocketAPI(
        browser_context, url, private_api, params, allowed_socket_origins_);
  #else
    return false;
  #endif
  }
  
  ui::SelectFilePolicy* ChromeContentBrowserClient::CreateSelectFilePolicy(
      WebContents* web_contents) {
    return new ChromeSelectFilePolicy(web_contents);
  }
  
  void ChromeContentBrowserClient::GetAdditionalAllowedSchemesForFileSystem(
      std::vector<std::string>* additional_allowed_schemes) {
    ContentBrowserClient::GetAdditionalAllowedSchemesForFileSystem(
        additional_allowed_schemes);
    additional_allowed_schemes->push_back(content::kChromeDevToolsScheme);
    additional_allowed_schemes->push_back(content::kChromeUIScheme);
    for (size_t i = 0; i < extra_parts_.size(); ++i) {
      extra_parts_[i]->GetAdditionalAllowedSchemesForFileSystem(
          additional_allowed_schemes);
    }
  }
  
  void ChromeContentBrowserClient::GetURLRequestAutoMountHandlers(
      std::vector<storage::URLRequestAutoMountHandler>* handlers) {
    for (size_t i = 0; i < extra_parts_.size(); ++i)
      extra_parts_[i]->GetURLRequestAutoMountHandlers(handlers);
  }
  
  void ChromeContentBrowserClient::GetAdditionalFileSystemBackends(
      content::BrowserContext* browser_context,
      const base::FilePath& storage_partition_path,
      ScopedVector<storage::FileSystemBackend>* additional_backends) {
  #if defined(OS_CHROMEOS)
    storage::ExternalMountPoints* external_mount_points =
        content::BrowserContext::GetMountPoints(browser_context);
    DCHECK(external_mount_points);
    chromeos::FileSystemBackend* backend = new chromeos::FileSystemBackend(
        new drive::FileSystemBackendDelegate,
        new chromeos::file_system_provider::BackendDelegate,
        new chromeos::MTPFileSystemBackendDelegate(storage_partition_path),
        browser_context->GetSpecialStoragePolicy(),
        external_mount_points,
        storage::ExternalMountPoints::GetSystemInstance());
    backend->AddSystemMountPoints();
    DCHECK(backend->CanHandleType(storage::kFileSystemTypeExternal));
    additional_backends->push_back(backend);
  #endif
  
    for (size_t i = 0; i < extra_parts_.size(); ++i) {
      extra_parts_[i]->GetAdditionalFileSystemBackends(
          browser_context, storage_partition_path, additional_backends);
    }
  }
  
  #if defined(OS_POSIX) && !defined(OS_MACOSX)
  void ChromeContentBrowserClient::GetAdditionalMappedFilesForChildProcess(
      const base::CommandLine& command_line,
      int child_process_id,
      FileDescriptorInfo* mappings) {
  #if defined(OS_ANDROID)
    base::FilePath data_path;
    PathService::Get(ui::DIR_RESOURCE_PAKS_ANDROID, &data_path);
    DCHECK(!data_path.empty());
  
    int flags = base::File::FLAG_OPEN | base::File::FLAG_READ;
    base::FilePath chrome_resources_pak =
        data_path.AppendASCII("chrome_100_percent.pak");
    base::File file(chrome_resources_pak, flags);
    DCHECK(file.IsValid());
    mappings->Transfer(kAndroidChrome100PercentPakDescriptor,
                       base::ScopedFD(file.TakePlatformFile()));
  
    const std::string locale = GetApplicationLocale();
    base::FilePath locale_pak = ResourceBundle::GetSharedInstance().
        GetLocaleFilePath(locale, false);
    file.Initialize(locale_pak, flags);
    DCHECK(file.IsValid());
    mappings->Transfer(kAndroidLocalePakDescriptor,
                       base::ScopedFD(file.TakePlatformFile()));
  
    base::FilePath resources_pack_path;
    PathService::Get(chrome::FILE_RESOURCES_PACK, &resources_pack_path);
    file.Initialize(resources_pack_path, flags);
    DCHECK(file.IsValid());
    mappings->Transfer(kAndroidUIResourcesPakDescriptor,
                       base::ScopedFD(file.TakePlatformFile()));
  
    if (breakpad::IsCrashReporterEnabled()) {
      file = breakpad::CrashDumpManager::GetInstance()->CreateMinidumpFile(
                 child_process_id);
      if (file.IsValid()) {
        mappings->Transfer(kAndroidMinidumpDescriptor,
                           base::ScopedFD(file.TakePlatformFile()));
      } else {
        LOG(ERROR) << "Failed to create file for minidump, crash reporting will "
                   "be disabled for this process.";
      }
    }
  
    base::FilePath app_data_path;
    PathService::Get(base::DIR_ANDROID_APP_DATA, &app_data_path);
    DCHECK(!app_data_path.empty());
  
    flags = base::File::FLAG_OPEN | base::File::FLAG_READ;
    base::FilePath icudata_path =
        app_data_path.AppendASCII(base::i18n::kIcuDataFileName);
    base::File icudata_file(icudata_path, flags);
    DCHECK(icudata_file.IsValid());
    mappings->Transfer(kAndroidICUDataDescriptor,
                       base::ScopedFD(icudata_file.TakePlatformFile()));
  
  #ifdef V8_USE_EXTERNAL_STARTUP_DATA
    base::FilePath v8_data_path;
    PathService::Get(base::DIR_ANDROID_APP_DATA, &v8_data_path);
    DCHECK(!v8_data_path.empty());
  
    int file_flags = base::File::FLAG_OPEN | base::File::FLAG_READ;
    base::FilePath v8_natives_data_path =
        v8_data_path.AppendASCII(gin::IsolateHolder::kNativesFileName);
    base::FilePath v8_snapshot_data_path =
        v8_data_path.AppendASCII(gin::IsolateHolder::kSnapshotFileName);
    base::File v8_natives_data_file(v8_natives_data_path, file_flags);
    base::File v8_snapshot_data_file(v8_snapshot_data_path, file_flags);
    DCHECK(v8_natives_data_file.IsValid());
    DCHECK(v8_snapshot_data_file.IsValid());
    mappings->Transfer(kV8NativesDataDescriptor,
                       base::ScopedFD(v8_natives_data_file.TakePlatformFile()));
    mappings->Transfer(kV8SnapshotDataDescriptor,
                       base::ScopedFD(v8_snapshot_data_file.TakePlatformFile()));
  #endif  // V8_USE_EXTERNAL_STARTUP_DATA
  
  #else
    int crash_signal_fd = GetCrashSignalFD(command_line);
    if (crash_signal_fd >= 0) {
      mappings->Share(kCrashDumpSignal, crash_signal_fd);
    }
  #endif  // defined(OS_ANDROID)
  }
  #endif  // defined(OS_POSIX) && !defined(OS_MACOSX)
  
  #if defined(OS_WIN)
  const wchar_t* ChromeContentBrowserClient::GetResourceDllName() {
    return chrome::kBrowserResourcesDll;
  }
  
  void ChromeContentBrowserClient::PreSpawnRenderer(
      sandbox::TargetPolicy* policy,
      bool* success) {
    // This code is duplicated in nacl_exe_win_64.cc.
    // Allow the server side of a pipe restricted to the "chrome.nacl."
    // namespace so that it cannot impersonate other system or other chrome
    // service pipes.
    sandbox::ResultCode result = policy->AddRule(
        sandbox::TargetPolicy::SUBSYS_NAMED_PIPES,
        sandbox::TargetPolicy::NAMEDPIPES_ALLOW_ANY,
        L"\\\\.\\pipe\\chrome.nacl.*");
    if (result != sandbox::SBOX_ALL_OK) {
      *success = false;
      return;
    }
  
    // Renderers need to send named pipe handles and shared memory
    // segment handles to NaCl loader processes.
    result = policy->AddRule(sandbox::TargetPolicy::SUBSYS_HANDLES,
                             sandbox::TargetPolicy::HANDLES_DUP_ANY,
                             L"File");
    if (result != sandbox::SBOX_ALL_OK) {
      *success = false;
      return;
    }
  }
  #endif
  
  bool ChromeContentBrowserClient::CheckMediaAccessPermission(
      content::BrowserContext* browser_context,
      const GURL& security_origin,
      content::MediaStreamType type) {
    return MediaCaptureDevicesDispatcher::GetInstance()
        ->CheckMediaAccessPermission(
            browser_context, security_origin, type);
  }
  
  content::DevToolsManagerDelegate*
  ChromeContentBrowserClient::GetDevToolsManagerDelegate() {
  #if defined(OS_ANDROID)
    return new DevToolsManagerDelegateAndroid();
  #else
    return new ChromeDevToolsManagerDelegate();
  #endif
  }
  
  bool ChromeContentBrowserClient::IsPluginAllowedToCallRequestOSFileHandle(
      content::BrowserContext* browser_context,
      const GURL& url) {
  #if defined(ENABLE_PLUGINS) && defined(ENABLE_EXTENSIONS)
    return ChromeContentBrowserClientPluginsPart::
        IsPluginAllowedToCallRequestOSFileHandle(browser_context, url,
                                                 allowed_file_handle_origins_);
  #else
    return false;
  #endif
  }
  
  bool ChromeContentBrowserClient::IsPluginAllowedToUseDevChannelAPIs(
      content::BrowserContext* browser_context,
      const GURL& url) {
  #if defined(ENABLE_PLUGINS) && defined(ENABLE_EXTENSIONS)
    return ChromeContentBrowserClientPluginsPart::
        IsPluginAllowedToUseDevChannelAPIs(browser_context, url,
                                           allowed_dev_channel_origins_);
  #else
    return false;
  #endif
  }
  
  net::CookieStore*
  ChromeContentBrowserClient::OverrideCookieStoreForRenderProcess(
      int render_process_id) {
    DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
    if (!prerender_tracker_)
      return NULL;
    return prerender_tracker_->GetPrerenderCookieStoreForRenderProcess(
                                   render_process_id).get();
  }
  
  #if defined(ENABLE_WEBRTC)
  void ChromeContentBrowserClient::MaybeCopyDisableWebRtcEncryptionSwitch(
      base::CommandLine* to_command_line,
      const base::CommandLine& from_command_line,
      VersionInfo::Channel channel) {
  #if defined(OS_ANDROID)
    const VersionInfo::Channel kMaxDisableEncryptionChannel =
        VersionInfo::CHANNEL_BETA;
  #else
    const VersionInfo::Channel kMaxDisableEncryptionChannel =
        VersionInfo::CHANNEL_DEV;
  #endif
    if (channel <= kMaxDisableEncryptionChannel) {
      static const char* const kWebRtcDevSwitchNames[] = {
        switches::kDisableWebRtcEncryption,
      };
      to_command_line->CopySwitchesFrom(from_command_line,
                                        kWebRtcDevSwitchNames,
                                        arraysize(kWebRtcDevSwitchNames));
    }
  }
  #endif  // defined(ENABLE_WEBRTC)
  
  }  // namespace chrome
  