Implement disabling and enabling media tracks

media/mojo/services/mojo_demuxer_stream_adapter.h

 // Copyright 2014 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_MOJO_SERVICES_MOJO_DEMUXER_STREAM_ADAPTER_H_
 #define MEDIA_MOJO_SERVICES_MOJO_DEMUXER_STREAM_ADAPTER_H_
 
 #include <queue>
 
 #include "base/macros.h"
@@ skipping 23 matching lines @@
   ~MojoDemuxerStreamAdapter() override;
 
   // DemuxerStream implementation.
   void Read(const ReadCB& read_cb) override;
   AudioDecoderConfig audio_decoder_config() override;
   VideoDecoderConfig video_decoder_config() override;
   Type type() const override;
   void EnableBitstreamConverter() override;
   bool SupportsConfigChanges() override;
   VideoRotation video_rotation() override;
+  bool enabled() const override;
+  void set_enabled(bool enabled, base::TimeDelta timestamp) override;
 
  private:
   void OnStreamReady(mojom::DemuxerStream::Type type,
                      mojo::ScopedDataPipeConsumerHandle pipe,
                      mojom::AudioDecoderConfigPtr audio_config,
                      mojom::VideoDecoderConfigPtr video_config);
 
   // The callback from |demuxer_stream_| that a read operation has completed.
   // |read_cb| is a callback from the client who invoked Read() on |this|.
   void OnBufferReady(mojom::DemuxerStream::Status status,
@@ skipping 14 matching lines @@
   // date AudioDecoderConfig yet. In that case we can't forward the results
   // on to the caller of Read() until OnAudioDecoderConfigChanged is observed.
   DemuxerStream::ReadCB read_cb_;
 
   // The current config.
   AudioDecoderConfig audio_config_;
   VideoDecoderConfig video_config_;
 
   DemuxerStream::Type type_;
 
+  bool enabled_ = true;

[chcunningham, 2016/06/03 01:38:49]

This class' style is to set defaults in the ctor

+
   // DataPipe for deserializing the data section of DecoderBuffers from.
   mojo::ScopedDataPipeConsumerHandle stream_pipe_;
 
   base::WeakPtrFactory<MojoDemuxerStreamAdapter> weak_factory_;
   DISALLOW_COPY_AND_ASSIGN(MojoDemuxerStreamAdapter);
 };
 
 }  // namespace media
 
 #endif  // MEDIA_MOJO_SERVICES_MOJO_DEMUXER_STREAM_ADAPTER_H_