Listen to the audio focus event for MSE/EME

media/base/android/media_player_android.h

Index: media/base/android/media_player_android.h
diff --git a/media/base/android/media_player_android.h b/media/base/android/media_player_android.h
index b339215ec8845cbc9f72c8cb53330bb161f8bdb5..d5e0895051199d3df2c2c8964c0cd8c0daf3cb43 100644
--- a/media/base/android/media_player_android.h
+++ b/media/base/android/media_player_android.h
@@ -9,7 +9,9 @@
 #include <string>
 
 #include "base/callback.h"
+#include "base/memory/weak_ptr.h"
 #include "base/time/time.h"
+#include "media/base/android/media_player_listener.h"
 #include "media/base/media_export.h"
 #include "ui/gl/android/scoped_java_surface.h"
 #include "url/gurl.h"
@@ -86,11 +88,29 @@ class MEDIA_EXPORT MediaPlayerAndroid {
                      const RequestMediaResourcesCB& request_media_resources_cb,
                      const GURL& frame_url);
 
+  // TODO(qinmin): Simplify the MediaPlayerListener class to only listen to
+  // media interrupt events. And have a separate child class to listen to all
+  // the events needed by MediaPlayerBridge. http://crbug.com/422597.
+  // MediaPlayerListener callbacks.
+  virtual void OnVideoSizeChanged(int width, int height);
+  virtual void OnMediaError(int error_type);
+  virtual void OnBufferingUpdate(int percent);
+  virtual void OnPlaybackComplete();
+  virtual void OnMediaInterrupted();
+  virtual void OnSeekComplete();
+  virtual void OnMediaPrepared();
+
+  // Attach/Detaches |listener_| for listening to all the events.
+  void AttachListener(jobject j_media_player);

[xhwang, 2014/10/14 18:23:30]

It seems |j_media_player| can be NULL here. What does it mean to have a null or
non-null |j_media_player|? It's not obvious that the |j_media_player| can also
listen to those events directly. Some comments would be helpful.

[qinmin, 2014/10/14 21:55:51]

Done.

+  void DetachListener();
+
   MediaPlayerManager* manager() { return manager_; }
 
   RequestMediaResourcesCB request_media_resources_cb_;
 
  private:
+  friend class MediaPlayerListener;
+
   // Player ID assigned to this player.
   int player_id_;
 
@@ -100,6 +120,13 @@ class MEDIA_EXPORT MediaPlayerAndroid {
   // Url for the frame that contains this player.
   GURL frame_url_;
 
+  // Listener object that listens to all the media player events.
+  scoped_ptr<MediaPlayerListener> listener_;
+
+  // Weak pointer passed to |listener_| for callbacks.
+  // NOTE: Weak pointers must be invalidated before all other member variables.
+  base::WeakPtrFactory<MediaPlayerAndroid> weak_factory_;
+
   DISALLOW_COPY_AND_ASSIGN(MediaPlayerAndroid);
 };