work-in-progress patch to fix context lost black video

content/renderer/media/android/webmediaplayer_android.h

Index: content/renderer/media/android/webmediaplayer_android.h
diff --git a/content/renderer/media/android/webmediaplayer_android.h b/content/renderer/media/android/webmediaplayer_android.h
index d338a4cc343c6b5fef57be40392a8d44f98f81c6..3415608773c19d7ac7c9d773fe42464aee2e3183 100644
--- a/content/renderer/media/android/webmediaplayer_android.h
+++ b/content/renderer/media/android/webmediaplayer_android.h
@@ -13,6 +13,7 @@
 #include "base/memory/ref_counted.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/memory/weak_ptr.h"
+#include "base/synchronization/waitable_event.h"
 #include "base/threading/thread_checker.h"
 #include "base/time/default_tick_clock.h"
 #include "base/time/time.h"
@@ -72,7 +73,8 @@ class WebContentDecryptionModuleImpl;
 // player.
 class WebMediaPlayerAndroid : public blink::WebMediaPlayer,
                               public cc::VideoFrameProvider,
-                              public RenderFrameObserver {
+                              public RenderFrameObserver,
+                              public StreamTextureFactoryContextObserver {
  public:
   // Construct a WebMediaPlayerAndroid object. This class communicates with the
   // MediaPlayerAndroid object in the browser process through |proxy|.
@@ -199,6 +201,9 @@ class WebMediaPlayerAndroid : public blink::WebMediaPlayer,
   void OnMediaPlayerPause();
   void OnRequestFullscreen();
 
+  // StreamTextureFactoryContextObserver implementation.
+  virtual void ResetStreamTextureProxy() OVERRIDE;
+
   // Called when the player is released.
   virtual void OnPlayerReleased();
 
@@ -404,28 +409,18 @@ class WebMediaPlayerAndroid : public blink::WebMediaPlayer,
   // point for when the mailbox was produced.
   gpu::Mailbox texture_mailbox_;
 
-  // Stream texture ID allocated to the video.
-  unsigned int stream_id_;
-
   // Whether the mediaplayer is playing.
   bool is_playing_;
 
   // Whether media player needs to re-establish the surface texture peer.
   bool needs_establish_peer_;
 
-  // Whether |stream_texture_proxy_| is initialized.
-  bool stream_texture_proxy_initialized_;
-
   // Whether the video size info is available.
   bool has_size_info_;
 
   // Object for allocating stream textures.
   scoped_refptr<StreamTextureFactory> stream_texture_factory_;
 
-  // Object for calling back the compositor thread to repaint the video when a
-  // frame available. It should be initialized on the compositor thread.
-  ScopedStreamTextureProxy stream_texture_proxy_;
-
   // Whether media player needs external surface.
   // Only used for the VIDEO_HOLE logic.
   bool needs_external_surface_;
@@ -433,10 +428,21 @@ class WebMediaPlayerAndroid : public blink::WebMediaPlayer,
   // Whether valid metadata are available
   bool has_valid_metadata_;
 
+  base::Lock client_lock_;
+
   // A pointer back to the compositor to inform it about state changes. This is
   // not NULL while the compositor is actively using this webmediaplayer.
+  // Protected by |client_lock_|.
   cc::VideoFrameProvider::Client* video_frame_provider_client_;
 
+  // Object for calling back the compositor thread to repaint the video when a
+  // frame available. It should be initialized on the compositor thread.
+  // Protected by |client_lock_|.
+  ScopedStreamTextureProxy stream_texture_proxy_;
+
+  // Stream texture ID allocated to the video. Protected by |client_lock_|.
+  unsigned int stream_id_;
+
   scoped_ptr<cc_blink::WebLayerImpl> video_weblayer_;
 
 #if defined(VIDEO_HOLE)