Revert of Allow muting/unmuting audio through media track API

media/base/media_tracks.h

Index: media/base/media_tracks.h
diff --git a/media/base/media_tracks.h b/media/base/media_tracks.h
index b45f81dd7b37cbb522b36576867360c35bd215e6..4e0fbb0fc1f88195ce14cc05d14a424924be4d5d 100644
--- a/media/base/media_tracks.h
+++ b/media/base/media_tracks.h
@@ -17,47 +17,30 @@
 namespace media {
 
 class AudioDecoderConfig;
-class DemuxerStream;
 class VideoDecoderConfig;
 
 class MEDIA_EXPORT MediaTracks {
  public:
   typedef std::vector<scoped_ptr<MediaTrack>> MediaTracksCollection;
-  typedef std::map<unsigned, const DemuxerStream*> TrackIdToDemuxStreamMap;
 
   MediaTracks();
   ~MediaTracks();
 
   // Callers need to ensure that track id is unique.
-  const MediaTrack* AddAudioTrack(const AudioDecoderConfig& config,
-                                  const std::string& id,
-                                  const std::string& kind,
-                                  const std::string& label,
-                                  const std::string& language);
+  void AddAudioTrack(const AudioDecoderConfig& config,
+                     const std::string& id,
+                     const std::string& kind,
+                     const std::string& label,
+                     const std::string& language);
   // Callers need to ensure that track id is unique.
-  const MediaTrack* AddVideoTrack(const VideoDecoderConfig& config,
-                                  const std::string& id,
-                                  const std::string& kind,
-                                  const std::string& label,
-                                  const std::string& language);
+  void AddVideoTrack(const VideoDecoderConfig& config,
+                     const std::string& id,
+                     const std::string& kind,
+                     const std::string& label,
+                     const std::string& language);
 
   const MediaTracksCollection& tracks() const { return tracks_; }
 
-  // TODO(servolk,wolenetz): Consider refactoring media track creation in MSE to
-  // simplify track id to DemuxerStream mapping. crbug.com/604088
-
-  // Notifies MediaTracks that a given media |track| object is backed by the
-  // given DemuxerStream |stream| object.
-  void SetDemuxerStreamForMediaTrack(const MediaTrack* track,
-                                     const DemuxerStream* stream);
-  // Notifies MediaTracks that external (blink) track ids have been assigned to
-  // the media |tracks_|. The size and ordering of |track_ids| must match the
-  // size and ordering of tracks in the |tracks_| collection, and
-  // |track_to_demux_stream_map_| must have an entry for each track in |tracks_|
-  // (set by SetDemuxerStreamForMediaTrack()).
-  TrackIdToDemuxStreamMap OnTrackIdsAssigned(
-      const std::vector<unsigned>& track_ids) const;
-
   const AudioDecoderConfig& getAudioConfig(const std::string& id) const;
   const VideoDecoderConfig& getVideoConfig(const std::string& id) const;
 
@@ -71,10 +54,6 @@ class MEDIA_EXPORT MediaTracks {
   std::map<std::string, AudioDecoderConfig> audio_configs_;
   std::map<std::string, VideoDecoderConfig> video_configs_;
 
-  typedef std::map<const MediaTrack*, const DemuxerStream*>
-      TrackToDemuxStreamMap;
-  TrackToDemuxStreamMap track_to_demux_stream_map_;
-
   DISALLOW_COPY_AND_ASSIGN(MediaTracks);
 };