Implement MediaSession on top of the WebMediaPlayerDelegate.

media/blink/webmediaplayer_impl.h

 // Copyright 2013 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_BLINK_WEBMEDIAPLAYER_IMPL_H_
 #define MEDIA_BLINK_WEBMEDIAPLAYER_IMPL_H_
 
 #include <stdint.h>
 
 #include <string>
@@ skipping 176 matching lines @@
   void OnPipelineError(PipelineStatus error);
   void OnPipelineMetadata(PipelineMetadata metadata);
   void OnPipelineBufferingStateChanged(BufferingState buffering_state);
   void OnDemuxerOpened();
   void OnAddTextTrack(const TextTrackConfig& config,
                       const AddTextTrackDoneCB& done_cb);
 
   // WebMediaPlayerDelegate::Observer implementation.
   void OnHidden() override;
   void OnShown() override;
+  void OnPlay() override;
+  void OnPause() override;
+  void OnVolumeMultiplierUpdate(double multiplier) override;
 
 #if defined(OS_ANDROID)  // WMPI_CAST
   bool isRemote() const override;
   void requestRemotePlayback() override;
   void requestRemotePlaybackControl() override;
 
   void SetMediaPlayerManager(
       RendererMediaPlayerManagerInterface* media_player_manager);
   void OnRemotePlaybackEnded();
   void OnDisconnectedFromRemoteDevice(double t);
@@ skipping 220 matching lines @@
 
   scoped_ptr<blink::WebContentDecryptionModuleResult> set_cdm_result_;
 
   // Whether a CDM has been successfully attached.
   bool is_cdm_attached_;
 
 #if defined(OS_ANDROID)  // WMPI_CAST
   WebMediaPlayerCast cast_impl_;
 #endif
 
+  double volume_;
+  double volume_multiplier_;
+
   scoped_ptr<RendererFactory> renderer_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(WebMediaPlayerImpl);
 };
 
 }  // namespace media
 
 #endif  // MEDIA_BLINK_WEBMEDIAPLAYER_IMPL_H_