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

content/renderer/media/android/stream_texture_factory_synchronous_impl.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 CONTENT_RENDERER_MEDIA_ANDROID_STREAM_TEXTURE_FACTORY_SYNCHRONOUS_IMPL_H_
 #define CONTENT_RENDERER_MEDIA_ANDROID_STREAM_TEXTURE_FACTORY_SYNCHRONOUS_IMPL_H_
 
 #include "base/callback.h"
 #include "base/memory/ref_counted.h"
+#include "base/observer_list.h"
 #include "content/renderer/media/android/stream_texture_factory.h"
 
 namespace gfx {
 class SurfaceTexture;
 }
 
 namespace gpu {
 namespace gles2 {
 class GLES2Interface;
 }  //  namespace gles2
 }  //  namespace gpu
 
 namespace content {
 
 // Factory for when using synchronous compositor in Android WebView.
 class StreamTextureFactorySynchronousImpl : public StreamTextureFactory {
  public:
   class ContextProvider : public base::RefCountedThreadSafe<ContextProvider> {
    public:
     virtual scoped_refptr<gfx::SurfaceTexture> GetSurfaceTexture(
         uint32 stream_id) = 0;
 
     virtual gpu::gles2::GLES2Interface* ContextGL() = 0;
 
+    virtual void AddObserver(StreamTextureFactoryContextObserver* obs) = 0;
+    virtual void RemoveObserver(StreamTextureFactoryContextObserver* obs) = 0;
+
    protected:
     friend class base::RefCountedThreadSafe<ContextProvider>;
     virtual ~ContextProvider() {}
   };
 
   typedef base::Callback<scoped_refptr<ContextProvider>(void)>
       CreateContextProviderCallback;
 
   static scoped_refptr<StreamTextureFactorySynchronousImpl> Create(
       const CreateContextProviderCallback& try_create_callback,
       int frame_id);
 
   virtual StreamTextureProxy* CreateProxy() OVERRIDE;
   virtual void EstablishPeer(int32 stream_id, int player_id) OVERRIDE;
   virtual unsigned CreateStreamTexture(unsigned texture_target,
                                        unsigned* texture_id,
                                        gpu::Mailbox* texture_mailbox) OVERRIDE;
   virtual void SetStreamTextureSize(int32 stream_id,
                                     const gfx::Size& size) OVERRIDE;
   virtual gpu::gles2::GLES2Interface* ContextGL() OVERRIDE;
+  virtual void AddObserver(StreamTextureFactoryContextObserver* obs) OVERRIDE;
+  virtual void RemoveObserver(
+      StreamTextureFactoryContextObserver* obs) OVERRIDE;
 
  private:
   friend class base::RefCounted<StreamTextureFactorySynchronousImpl>;
   StreamTextureFactorySynchronousImpl(
       const CreateContextProviderCallback& try_create_callback,
       int frame_id);
   virtual ~StreamTextureFactorySynchronousImpl();
 
   CreateContextProviderCallback create_context_provider_callback_;
   scoped_refptr<ContextProvider> context_provider_;
   int frame_id_;
+  StreamTextureFactoryContextObserver* observer_;
 
   DISALLOW_IMPLICIT_CONSTRUCTORS(StreamTextureFactorySynchronousImpl);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_RENDERER_MEDIA_ANDROID_STREAM_TEXTURE_FACTORY_SYNCHRONOUS_IMPL_H_