Cast: deliver video frames on the IO thread

content/renderer/media/media_stream_video_track.h

Index: content/renderer/media/media_stream_video_track.h
diff --git a/content/renderer/media/media_stream_video_track.h b/content/renderer/media/media_stream_video_track.h
index 9fa8125d27b27f7184afc300e006db3ddecf44a2..098794c3df87fa280a0e64644eb690f55193d9e7 100644
--- a/content/renderer/media/media_stream_video_track.h
+++ b/content/renderer/media/media_stream_video_track.h
@@ -48,16 +48,11 @@ class CONTENT_EXPORT MediaStreamVideoTrack : public MediaStreamTrack {
        bool enabled);
   virtual ~MediaStreamVideoTrack();
 
-  // Add |sink| to receive state changes and video frames on the main render
-  // thread.
-  virtual void AddSink(MediaStreamVideoSink* sink);
-  virtual void RemoveSink(MediaStreamVideoSink* sink);
-
   // Add |sink| to receive state changes on the main render thread and video
   // frames in the |callback| method on the IO-thread.
-  virtual void AddSink(MediaStreamSink* sink,
+  virtual void AddSink(MediaStreamVideoSink* sink,
                        const VideoCaptureDeliverFrameCB& callback);
-  virtual void RemoveSink(MediaStreamSink* sink);
+  virtual void RemoveSink(MediaStreamVideoSink* sink);
 
   virtual void SetEnabled(bool enabled) OVERRIDE;
   virtual void Stop() OVERRIDE;