anchor.diff:        url '$urlBase/dev/release/${revisions['dev']}/$ia32File'
         sha256 '${hashes['dev'][ia32File]}'
       end
  +
  +    resource 'content_shell' do
  +      url '$urlBase/dev/release/${revisions['dev']}/$contentShellFile'
  +      sha256 '${hashes['dev'][contentShellFile]}'
  +    end
  +
  +    resource 'dartium' do
  +      url '$urlBase/dev/release/${revisions['dev']}/$dartiumFile'
  +      sha256 '${hashes['dev'][dartiumFile]}'
  +    end
  +  end
  +
  +  resource 'content_shell' do
  +    url '$urlBase/stable/release/${revisions['stable']}/$contentShellFile'
  +    sha256 '${hashes['stable'][contentShellFile]}'
  +  end
  +
  +  resource 'dartium' do
  +    url '$urlBase/stable/release/${revisions['stable']}/$dartiumFile'
  +    sha256 '${hashes['stable'][dartiumFile]}'
     end
   
     def install
       libexec.install Dir['*']
       bin.install_symlink "#{libexec}/bin/dart"
       bin.write_exec_script Dir["#{libexec}/bin/{pub,docgen,dart?*}"]
  +
  +    if build.with? 'content-shell'
  +      dartium_binary = 'Chromium.app/Contents/MacOS/Chromium'
  +      prefix.install resource('dartium')
  +      (bin+"dartium").write shim_script dartium_binary
  +    end
  +
  +    if build.with? 'content-shell'
  +      content_shell_binary = 'Content Shell.app/Contents/MacOS/Content Shell'
  +      prefix.install resource('content_shell')
  +      (bin+"content_shell").write shim_script content_shell_binary
  +    end
  +  end
  +
  +  def shim_script target
  +    <<-EOS.undent
  +      #!/bin/bash
  +      exec "#{prefix}/#{target}" "\$@"
  +    EOS
     end
   
     def caveats; <<-EOS.undent
       Please note the path to the Dart SDK:
         #{opt_libexec}
  +
  +    --with-dartium:
  +      To use with IntelliJ, set the Dartium execute home to:
  +        #{prefix}/Chromium.app
       EOS
     end
   
  
positive.code: 
      resource 'content_shell' do
        url '$urlBase/dev/release/${revisions['dev']}/$contentShellFile'
        version '$devVersion'
        sha256 '${hashes['dev'][contentShellFile]}'
      end
    end
  
    resource 'content_shell' do
      url '$urlBase/stable/release/${revisions['stable']}/$contentShellFile'
      version '$stableVersion'
      sha256 '${hashes['stable'][contentShellFile]}'
    end
  
  
negative.code:   final options = parser.parse(args);
    final revision = options['revision'];
    final channel = options['channel'];
    if ([revision, channel].contains(null)) {
      print("Usage: update_homebrew.dart -r revision -c channel [-k ssh_key]\n"
          "  ssh_key should allow pushes to ${GITHUB_REPO} on github");
      return;
    }
  
    final key = options['key'];
    if (key != null) {
      final sshWrapper = Platform.script.resolve('ssh_with_key').toFilePath();
      gitEnvironment = {'GIT_SSH': sshWrapper, 'SSH_KEY_PATH': key};
    }
  
    Chain.capture(() async {
      var tempDir = await Directory.systemTemp.createTemp('update_homebrew');
  