Make rendering of MediaStreams reflect changes to its set of tracks.

content/renderer/media/webmediaplayer_ms.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 CONTENT_RENDERER_MEDIA_WEBMEDIAPLAYER_MS_H_
 #define CONTENT_RENDERER_MEDIA_WEBMEDIAPLAYER_MS_H_
 
 #include <memory>
 #include <string>
 
 #include "base/macros.h"
 #include "base/memory/weak_ptr.h"
 #include "base/single_thread_task_runner.h"
 #include "base/synchronization/lock.h"
 #include "base/threading/thread_checker.h"
 #include "content/common/content_export.h"
+#include "content/renderer/media/media_stream.h"
 #include "media/blink/webmediaplayer_delegate.h"
 #include "media/blink/webmediaplayer_util.h"
 #include "media/renderers/gpu_video_accelerator_factories.h"
 #include "media/renderers/skcanvas_video_renderer.h"
 #include "third_party/WebKit/public/platform/WebMediaPlayer.h"
 #include "url/origin.h"
 
 namespace blink {
 class WebLocalFrame;
 class WebMediaPlayerClient;
@@ skipping 28 matching lines @@
 // Renderer process.
 //
 // WebMediaPlayerMS works with multiple objects, the most important ones are:
 //
 // MediaStreamVideoRenderer
 //   provides video frames for rendering.
 //
 // blink::WebMediaPlayerClient
 //   WebKit client of this media player object.
 class CONTENT_EXPORT WebMediaPlayerMS
-    : public NON_EXPORTED_BASE(blink::WebMediaPlayer),
+    : public NON_EXPORTED_BASE(MediaStreamObserver),
+      public NON_EXPORTED_BASE(blink::WebMediaPlayer),
       public NON_EXPORTED_BASE(media::WebMediaPlayerDelegate::Observer),
       public NON_EXPORTED_BASE(base::SupportsWeakPtr<WebMediaPlayerMS>) {
  public:
   // Construct a WebMediaPlayerMS with reference to the client, and
   // a MediaStreamClient which provides MediaStreamVideoRenderer.
   // |delegate| must not be null.
   WebMediaPlayerMS(
       blink::WebLocalFrame* frame,
       blink::WebMediaPlayerClient* client,
       media::WebMediaPlayerDelegate* delegate,
@@ skipping 96 matching lines @@
                     int level,
                     int internalformat,
                     unsigned format,
                     unsigned type,
                     int xoffset,
                     int yoffset,
                     int zoffset,
                     bool flip_y,
                     bool premultiply_alpha) override;
 
+  // MediaStreamObserver implementation
+  void TrackAdded(const blink::WebMediaStreamTrack& track) override;
+  void TrackRemoved(const blink::WebMediaStreamTrack& track) override;
+
  private:
   friend class WebMediaPlayerMSTest;
 
   void OnFirstFrameReceived(media::VideoRotation video_rotation,
                             bool is_opaque);
   void OnOpacityChanged(bool is_opaque);
   void OnRotationChanged(media::VideoRotation video_rotation, bool is_opaque);
 
   // Need repaint due to state change.
   void RepaintInternal();
 
   // The callback for source to report error.
   void OnSourceError();
 
   // Helpers that set the network/ready state and notifies the client if
   // they've changed.
   void SetNetworkState(blink::WebMediaPlayer::NetworkState state);
   void SetReadyState(blink::WebMediaPlayer::ReadyState state);
 
   // Getter method to |client_|.
   blink::WebMediaPlayerClient* get_client() { return client_; }
 
+  // To be run when tracks are added or removed.
+  void Reload();
+  void ReloadVideo();
+  void ReloadAudio();
+
   blink::WebLocalFrame* const frame_;
 
   blink::WebMediaPlayer::NetworkState network_state_;
   blink::WebMediaPlayer::ReadyState ready_state_;
 
   const blink::WebTimeRanges buffered_;
 
   blink::WebMediaPlayerClient* const client_;
 
   // WebMediaPlayer notifies the |delegate_| of playback state changes using
@@ skipping 45 matching lines @@
   // The last volume received by setVolume() and the last volume multiplier from
   // OnVolumeMultiplierUpdate().  The multiplier is typical 1.0, but may be less
   // if the WebMediaPlayerDelegate has requested a volume reduction (ducking)
   // for a transient sound.  Playout volume is derived by volume * multiplier.
   double volume_;
   double volume_multiplier_;
 
   // True if playback should be started upon the next call to OnShown(). Only
   // used on Android.
   bool should_play_upon_shown_;
+  blink::WebMediaStream web_stream_;
+  // IDs of the tracks currently played.
+  blink::WebString current_video_track_id_;
+  blink::WebString current_audio_track_id_;
 
   DISALLOW_COPY_AND_ASSIGN(WebMediaPlayerMS);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_RENDERER_MEDIA_WEBMEDIAPLAYER_MS_H_