Implement disabling and enabling media tracks

media/base/demuxer.h

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef MEDIA_BASE_DEMUXER_H_
 #define MEDIA_BASE_DEMUXER_H_
 
 #include <stdint.h>
 
 #include <memory>
 #include <vector>
 
 #include "base/macros.h"
 #include "base/time/time.h"
 #include "media/base/data_source.h"
 #include "media/base/demuxer_stream.h"
 #include "media/base/demuxer_stream_provider.h"
 #include "media/base/eme_constants.h"
 #include "media/base/media_export.h"
+#include "media/base/media_track.h"
 #include "media/base/pipeline_status.h"
 #include "media/base/ranges.h"
 
 namespace media {
 
 class TextTrackConfig;
 class MediaTracks;
 
 class MEDIA_EXPORT DemuxerHost {
  public:
@@ skipping 98 matching lines @@
   virtual base::TimeDelta GetStartTime() const = 0;
 
   // Returns Time represented by presentation timestamp 0.
   // If the timstamps are not associated with a Time, then
   // a null Time is returned.
   virtual base::Time GetTimelineOffset() const = 0;
 
   // Returns the memory usage in bytes for the demuxer.
   virtual int64_t GetMemoryUsage() const = 0;
 
+  virtual void OnEnabledAudioTracksChanged(
+      const std::vector<MediaTrack::Id>& track_ids,
+      base::TimeDelta currTime) = 0;
+  // |track_ids| is either empty or contains a single video track id.

[chcunningham, 2016/06/24 23:32:55]

New line above this comment?

[servolk, 2016/06/25 00:36:33]

Done.

+  virtual void OnSelectedVideoTrackChanged(
+      const std::vector<MediaTrack::Id>& track_ids,
+      base::TimeDelta currTime) = 0;
+
  private:
   DISALLOW_COPY_AND_ASSIGN(Demuxer);
 };
 
 }  // namespace media
 
 #endif  // MEDIA_BASE_DEMUXER_H_