Revert of Allow muting/unmuting audio through media track API

media/base/pipeline_impl.h

 // Copyright (c) 2016 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_PIPELINE_IMPL_H_
 #define MEDIA_BASE_PIPELINE_IMPL_H_
 
 #include "base/gtest_prod_util.h"
 #include "base/macros.h"
 #include "base/memory/ref_counted.h"
@@ skipping 93 matching lines @@
               const PipelineStatusCB& seek_cb) override;
   float GetVolume() const override;
   void SetVolume(float volume) override;
   base::TimeDelta GetMediaTime() const override;
   Ranges<base::TimeDelta> GetBufferedTimeRanges() const override;
   base::TimeDelta GetMediaDuration() const override;
   bool DidLoadingProgress() override;
   PipelineStatistics GetStatistics() const override;
   void SetCdm(CdmContext* cdm_context,
               const CdmAttachedCB& cdm_attached_cb) override;
-  void OnEnabledAudioStreamsChanged(
-      const std::vector<const DemuxerStream*>& enabledAudioStreams) override;
-  void OnSelectedVideoStreamChanged(
-      const DemuxerStream* selectedVideoStream) override;
 
  private:
   friend class MediaLog;
   friend class PipelineImplTest;
 
   // Pipeline states, as described above.
   enum State {
     kCreated,
     kInitDemuxer,
     kInitRenderer,
@@ skipping 213 matching lines @@
   // Declared last so that weak pointers will be invalidated before all other
   // member variables.
   base::WeakPtrFactory<PipelineImpl> weak_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(PipelineImpl);
 };
 
 }  // namespace media
 
 #endif  // MEDIA_BASE_PIPELINE_IMPL_H_