Implement disabling and enabling media tracks

media/base/android/media_url_demuxer.h

Index: media/base/android/media_url_demuxer.h
diff --git a/media/base/android/media_url_demuxer.h b/media/base/android/media_url_demuxer.h
index 796403819fd7830452003e54487437e950aca28a..dbd8ee6026fc862724f30e5924d1c6640484f795 100644
--- a/media/base/android/media_url_demuxer.h
+++ b/media/base/android/media_url_demuxer.h
@@ -50,6 +50,10 @@ class MediaUrlDemuxer : public Demuxer {
   base::TimeDelta GetStartTime() const override;
   base::Time GetTimelineOffset() const override;
   int64_t GetMemoryUsage() const override;
+  void OnEnabledAudioTracksChanged(const std::vector<MediaTrack::Id>& track_ids,
+                                   base::TimeDelta currTime) override;
+  void OnSelectedVideoTrackChanged(const std::vector<MediaTrack::Id>& track_ids,
+                                   base::TimeDelta currTime) override;
 
  private:
   GURL url_;