remove VideoDeviceError and AudioDeviceError for media stream.

content/renderer/media/media_stream_dispatcher_eventhandler.h

Index: content/renderer/media/media_stream_dispatcher_eventhandler.h
===================================================================
--- content/renderer/media/media_stream_dispatcher_eventhandler.h	(revision 161798)
+++ content/renderer/media/media_stream_dispatcher_eventhandler.h	(working copy)
@@ -23,16 +23,6 @@
   // to the requested devices or no device is available.
   virtual void OnStreamGenerationFailed(int request_id) = 0;
 
-  // An error have occurred on a video device. This is called if a runtime
-  // error occurs.
-  virtual void OnVideoDeviceFailed(const std::string& label,
-                                   int index) = 0;
-
-  // An error have occurred on an audio device. This is called if a runtime
-  // error occurs.
-  virtual void OnAudioDeviceFailed(const std::string& label,
-                                   int index) = 0;
-
   // A new list of devices have been enumerated.
   virtual void OnDevicesEnumerated(
       int request_id,