prompt: We are currently solving the following issue within our repository. Here is the issue text:
  --- BEGIN ISSUE ---
  emphasize message when content renderer is not available
  
  Current behavior is confusing because the error is styled the same as the description:
  
  ![image](https://cloud.githubusercontent.com/assets/2367265/23562570/d50525d4-fff7-11e6-8644-98c28b9a6c7d.png)
  
  
  > Kolibri is unable to render this content
  
  This string should be rendered as an error message so it doesn't look like part of the content description. Recommend that we use a [non-dismissible alert](https://josephuspaye.github.io/Keen-UI/#/ui-alert) error:
  
  ![image](https://cloud.githubusercontent.com/assets/2367265/23562703/6ddf6a26-fff8-11e6-9b4c-45d2f3d7bcec.png)
  
  
  
  
  --- END ISSUE ---
  
  Below are some code segments, each from a relevant file. One or more of these files may contain bugs.
  --- BEGIN FILES ---
  Path: `kolibri/plugins/html5_app_renderer/kolibri_plugin.py`
  Content:
  ```
  1 from __future__ import absolute_import, print_function, unicode_literals
  2 
  3 from kolibri.content import hooks as content_hooks
  4 from kolibri.plugins.base import KolibriPluginBase
  5 
  6 
  7 class HTML5AppPlugin(KolibriPluginBase):
  8     pass
  9 
  10 
  11 class HTML5AppAsset(content_hooks.WebpackBundleHook):
  12     unique_slug = "html5_app_renderer_module"
  13     src_file = "assets/src/module.js"
  14     content_types_file = "assets/src/content_types.json"
  15
  ```
  
  Path: `kolibri/plugins/audio_mp3_render/kolibri_plugin.py`
  Content:
  ```
  1 from __future__ import absolute_import, print_function, unicode_literals
  2 
  3 from kolibri.content import hooks as content_hooks
  4 from kolibri.plugins.base import KolibriPluginBase
  5 
  6 
  7 class AudioMP3RenderPlugin(KolibriPluginBase):
  8     pass
  9 
  10 
  11 class AudioMP3RenderAsset(content_hooks.WebpackBundleHook):
  12     unique_slug = "audio_mp3_render_module"
  13     src_file = "assets/src/module.js"
  14     content_types_file = "assets/src/content_types.json"
  15
  ```
  
  Path: `kolibri/plugins/document_pdf_render/kolibri_plugin.py`
  Content:
  ```
  1 from __future__ import absolute_import, print_function, unicode_literals
  2 
  3 from kolibri.content import hooks as content_hooks
  4 from kolibri.plugins.base import KolibriPluginBase
  5 
  6 
  7 class DocumentPDFRenderPlugin(KolibriPluginBase):
  8     pass
  9 
  10 
  11 class DocumentPDFRenderAsset(content_hooks.WebpackBundleHook):
  12     unique_slug = "document_pdf_render_module"
  13     src_file = "assets/src/module.js"
  14     content_types_file = "assets/src/content_types.json"
  15
  ```
  --- END FILES ---
  
  Please first localize the bug based on the issue statement, and then generate a patch according to the `git diff` format fenced by three backticks.
  
  Here is an example:
  
  ```diff
  diff --git a/examples/server_async.py b/examples/server_async.py
  --- a/examples/server_async.py
  +++ b/examples/server_async.py
  @@ -313,4 +313,4 @@
   
   
   if __name__ == "__main__":
  -    asyncio.run(run_async_server("."), debug=True)
  +    asyncio.run(run_async_server(), debug=True)
  diff --git a/examples/server_sync.py b/examples/server_sync.py
  --- a/examples/server_sync.py
  +++ b/examples/server_sync.py
  @@ -313,5 +313,5 @@
   
   
   if __name__ == "__main__":
  -    server = run_sync_server(".")
  +    server = run_sync_server()
       server.shutdown()
  
  ```
  
golden_diff: diff --git a/kolibri/plugins/audio_mp3_render/kolibri_plugin.py b/kolibri/plugins/audio_mp3_render/kolibri_plugin.py
  --- a/kolibri/plugins/audio_mp3_render/kolibri_plugin.py
  +++ b/kolibri/plugins/audio_mp3_render/kolibri_plugin.py
  @@ -8,7 +8,7 @@
       pass
   
   
  -class AudioMP3RenderAsset(content_hooks.WebpackBundleHook):
  +class AudioMP3RenderAsset(content_hooks.ContentRendererHook):
       unique_slug = "audio_mp3_render_module"
       src_file = "assets/src/module.js"
       content_types_file = "assets/src/content_types.json"
  diff --git a/kolibri/plugins/document_pdf_render/kolibri_plugin.py b/kolibri/plugins/document_pdf_render/kolibri_plugin.py
  --- a/kolibri/plugins/document_pdf_render/kolibri_plugin.py
  +++ b/kolibri/plugins/document_pdf_render/kolibri_plugin.py
  @@ -8,7 +8,7 @@
       pass
   
   
  -class DocumentPDFRenderAsset(content_hooks.WebpackBundleHook):
  +class DocumentPDFRenderAsset(content_hooks.ContentRendererHook):
       unique_slug = "document_pdf_render_module"
       src_file = "assets/src/module.js"
       content_types_file = "assets/src/content_types.json"
  diff --git a/kolibri/plugins/html5_app_renderer/kolibri_plugin.py b/kolibri/plugins/html5_app_renderer/kolibri_plugin.py
  --- a/kolibri/plugins/html5_app_renderer/kolibri_plugin.py
  +++ b/kolibri/plugins/html5_app_renderer/kolibri_plugin.py
  @@ -8,7 +8,7 @@
       pass
   
   
  -class HTML5AppAsset(content_hooks.WebpackBundleHook):
  +class HTML5AppAsset(content_hooks.ContentRendererHook):
       unique_slug = "html5_app_renderer_module"
       src_file = "assets/src/module.js"
       content_types_file = "assets/src/content_types.json"
  
verification_info: {"golden_diff": "diff --git a/kolibri/plugins/audio_mp3_render/kolibri_plugin.py b/kolibri/plugins/audio_mp3_render/kolibri_plugin.py\n--- a/kolibri/plugins/audio_mp3_render/kolibri_plugin.py\n+++ b/kolibri/plugins/audio_mp3_render/kolibri_plugin.py\n@@ -8,7 +8,7 @@\n     pass\n \n \n-class AudioMP3RenderAsset(content_hooks.WebpackBundleHook):\n+class AudioMP3RenderAsset(content_hooks.ContentRendererHook):\n     unique_slug = \"audio_mp3_render_module\"\n     src_file = \"assets/src/module.js\"\n     content_types_file = \"assets/src/content_types.json\"\ndiff --git a/kolibri/plugins/document_pdf_render/kolibri_plugin.py b/kolibri/plugins/document_pdf_render/kolibri_plugin.py\n--- a/kolibri/plugins/document_pdf_render/kolibri_plugin.py\n+++ b/kolibri/plugins/document_pdf_render/kolibri_plugin.py\n@@ -8,7 +8,7 @@\n     pass\n \n \n-class DocumentPDFRenderAsset(content_hooks.WebpackBundleHook):\n+class DocumentPDFRenderAsset(content_hooks.ContentRendererHook):\n     unique_slug = \"document_pdf_render_module\"\n     src_file = \"assets/src/module.js\"\n     content_types_file = \"assets/src/content_types.json\"\ndiff --git a/kolibri/plugins/html5_app_renderer/kolibri_plugin.py b/kolibri/plugins/html5_app_renderer/kolibri_plugin.py\n--- a/kolibri/plugins/html5_app_renderer/kolibri_plugin.py\n+++ b/kolibri/plugins/html5_app_renderer/kolibri_plugin.py\n@@ -8,7 +8,7 @@\n     pass\n \n \n-class HTML5AppAsset(content_hooks.WebpackBundleHook):\n+class HTML5AppAsset(content_hooks.ContentRendererHook):\n     unique_slug = \"html5_app_renderer_module\"\n     src_file = \"assets/src/module.js\"\n     content_types_file = \"assets/src/content_types.json\"\n", "issue": "emphasize message when content renderer is not available\n\r\nCurrent behavior is confusing because the error is styled the same as the description:\r\n\r\n![image](https://cloud.githubusercontent.com/assets/2367265/23562570/d50525d4-fff7-11e6-8644-98c28b9a6c7d.png)\r\n\r\n\r\n> Kolibri is unable to render this content\r\n\r\nThis string should be rendered as an error message so it doesn't look like part of the content description. Recommend that we use a [non-dismissible alert](https://josephuspaye.github.io/Keen-UI/#/ui-alert) error:\r\n\r\n![image](https://cloud.githubusercontent.com/assets/2367265/23562703/6ddf6a26-fff8-11e6-9b4c-45d2f3d7bcec.png)\r\n\r\n\r\n\n", "before_files": [{"content": "from __future__ import absolute_import, print_function, unicode_literals\n\nfrom kolibri.content import hooks as content_hooks\nfrom kolibri.plugins.base import KolibriPluginBase\n\n\nclass HTML5AppPlugin(KolibriPluginBase):\n    pass\n\n\nclass HTML5AppAsset(content_hooks.WebpackBundleHook):\n    unique_slug = \"html5_app_renderer_module\"\n    src_file = \"assets/src/module.js\"\n    content_types_file = \"assets/src/content_types.json\"\n", "path": "kolibri/plugins/html5_app_renderer/kolibri_plugin.py"}, {"content": "from __future__ import absolute_import, print_function, unicode_literals\n\nfrom kolibri.content import hooks as content_hooks\nfrom kolibri.plugins.base import KolibriPluginBase\n\n\nclass AudioMP3RenderPlugin(KolibriPluginBase):\n    pass\n\n\nclass AudioMP3RenderAsset(content_hooks.WebpackBundleHook):\n    unique_slug = \"audio_mp3_render_module\"\n    src_file = \"assets/src/module.js\"\n    content_types_file = \"assets/src/content_types.json\"\n", "path": "kolibri/plugins/audio_mp3_render/kolibri_plugin.py"}, {"content": "from __future__ import absolute_import, print_function, unicode_literals\n\nfrom kolibri.content import hooks as content_hooks\nfrom kolibri.plugins.base import KolibriPluginBase\n\n\nclass DocumentPDFRenderPlugin(KolibriPluginBase):\n    pass\n\n\nclass DocumentPDFRenderAsset(content_hooks.WebpackBundleHook):\n    unique_slug = \"document_pdf_render_module\"\n    src_file = \"assets/src/module.js\"\n    content_types_file = \"assets/src/content_types.json\"\n", "path": "kolibri/plugins/document_pdf_render/kolibri_plugin.py"}], "after_files": [{"content": "from __future__ import absolute_import, print_function, unicode_literals\n\nfrom kolibri.content import hooks as content_hooks\nfrom kolibri.plugins.base import KolibriPluginBase\n\n\nclass HTML5AppPlugin(KolibriPluginBase):\n    pass\n\n\nclass HTML5AppAsset(content_hooks.ContentRendererHook):\n    unique_slug = \"html5_app_renderer_module\"\n    src_file = \"assets/src/module.js\"\n    content_types_file = \"assets/src/content_types.json\"\n", "path": "kolibri/plugins/html5_app_renderer/kolibri_plugin.py"}, {"content": "from __future__ import absolute_import, print_function, unicode_literals\n\nfrom kolibri.content import hooks as content_hooks\nfrom kolibri.plugins.base import KolibriPluginBase\n\n\nclass AudioMP3RenderPlugin(KolibriPluginBase):\n    pass\n\n\nclass AudioMP3RenderAsset(content_hooks.ContentRendererHook):\n    unique_slug = \"audio_mp3_render_module\"\n    src_file = \"assets/src/module.js\"\n    content_types_file = \"assets/src/content_types.json\"\n", "path": "kolibri/plugins/audio_mp3_render/kolibri_plugin.py"}, {"content": "from __future__ import absolute_import, print_function, unicode_literals\n\nfrom kolibri.content import hooks as content_hooks\nfrom kolibri.plugins.base import KolibriPluginBase\n\n\nclass DocumentPDFRenderPlugin(KolibriPluginBase):\n    pass\n\n\nclass DocumentPDFRenderAsset(content_hooks.ContentRendererHook):\n    unique_slug = \"document_pdf_render_module\"\n    src_file = \"assets/src/module.js\"\n    content_types_file = \"assets/src/content_types.json\"\n", "path": "kolibri/plugins/document_pdf_render/kolibri_plugin.py"}]}