Allow cmdbuffer creation from compositor thread.

content/renderer/gpu/gpu_video_decode_accelerator_host.h

 // Copyright (c) 2011 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_GPU_GPU_VIDEO_DECODE_ACCELERATOR_HOST_H_
 #define CONTENT_RENDERER_GPU_GPU_VIDEO_DECODE_ACCELERATOR_HOST_H_
 
 #include <vector>
 
+#include "base/memory/weak_ptr.h"
 #include "base/threading/non_thread_safe.h"
 #include "ipc/ipc_channel.h"
 #include "media/video/video_decode_accelerator.h"
 
 class GpuChannelHost;
 
 // This class is used to talk to VideoDecodeAccelerator in the Gpu process
 // through IPC messages.
 class GpuVideoDecodeAcceleratorHost
     : public IPC::Channel::Listener,
       public media::VideoDecodeAccelerator,
-      public base::NonThreadSafe {
+      public base::NonThreadSafe,
+      public base::SupportsWeakPtr<GpuVideoDecodeAcceleratorHost> {
  public:
   // |channel| is used to send IPC messages to GPU process.
   GpuVideoDecodeAcceleratorHost(GpuChannelHost* channel,
                                 int32 decoder_route_id,
                                 media::VideoDecodeAccelerator::Client* client);
   virtual ~GpuVideoDecodeAcceleratorHost();
 
   // IPC::Channel::Listener implementation.
   virtual void OnChannelError() OVERRIDE;
   virtual bool OnMessageReceived(const IPC::Message& message) OVERRIDE;
@@ skipping 30 matching lines @@
   // attempting to use an outdated or reused route id.
   int32 decoder_route_id_;
 
   // Reference to the client that will receive callbacks from the decoder.
   media::VideoDecodeAccelerator::Client* client_;
 
   DISALLOW_COPY_AND_ASSIGN(GpuVideoDecodeAcceleratorHost);
 };
 
 #endif  // CONTENT_RENDERER_GPU_GPU_VIDEO_DECODE_ACCELERATOR_HOST_H_