MediaStream audio object graph untangling and clean-ups.

content/renderer/media/webrtc/media_stream_remote_audio_track.h

Index: content/renderer/media/webrtc/media_stream_remote_audio_track.h
diff --git a/content/renderer/media/webrtc/media_stream_remote_audio_track.h b/content/renderer/media/webrtc/media_stream_remote_audio_track.h
index e2a6eaa9dd98136685e51fa5d48d2fbfb3910531..de90dcaa2aeb2460c00b24ec1a4122a95fadc860 100644
--- a/content/renderer/media/webrtc/media_stream_remote_audio_track.h
+++ b/content/renderer/media/webrtc/media_stream_remote_audio_track.h
@@ -25,9 +25,11 @@ class MediaStreamRemoteAudioTrack : public MediaStreamAudioTrack {
       const blink::WebMediaStreamSource& source, bool enabled);
   ~MediaStreamRemoteAudioTrack() override;
 
+  // MediaStreamTrack overrides.
   void SetEnabled(bool enabled) override;
-  void Stop() override;
+  void Stop() final;
 
+  // MediaStreamAudioTrack overrides.
   void AddSink(MediaStreamAudioSink* sink) override;
   void RemoveSink(MediaStreamAudioSink* sink) override;
   media::AudioParameters GetOutputFormat() const override;
@@ -44,6 +46,7 @@ class MediaStreamRemoteAudioTrack : public MediaStreamAudioTrack {
 // Inheriting from ExtraData directly since MediaStreamAudioSource has
 // too much unrelated bloat.
 // TODO(tommi): MediaStreamAudioSource needs refactoring.
+// TODO(miu): On it!  ;-)
 class MediaStreamRemoteAudioSource
     : public blink::WebMediaStreamSource::ExtraData {
  public: