Clarify ownership of GpuVideoDecodeAcceleratorHost and avoid crash on context loss.

content/common/gpu/client/gpu_video_decode_accelerator_host.h

Index: content/common/gpu/client/gpu_video_decode_accelerator_host.h
diff --git a/content/common/gpu/client/gpu_video_decode_accelerator_host.h b/content/common/gpu/client/gpu_video_decode_accelerator_host.h
index e33129fa45fd712ee1b0a6f6c4338487a717d038..b46310ace1af5226de30cea94fb6945b347b7059 100644
--- a/content/common/gpu/client/gpu_video_decode_accelerator_host.h
+++ b/content/common/gpu/client/gpu_video_decode_accelerator_host.h
@@ -25,7 +25,6 @@ class GpuVideoDecodeAcceleratorHost
   GpuVideoDecodeAcceleratorHost(GpuChannelHost* channel,
                                 int32 decoder_route_id,
                                 media::VideoDecodeAccelerator::Client* client);
-  virtual ~GpuVideoDecodeAcceleratorHost();
 
   // IPC::Listener implementation.
   virtual void OnChannelError() OVERRIDE;
@@ -42,6 +41,9 @@ class GpuVideoDecodeAcceleratorHost
   virtual void Destroy() OVERRIDE;
 
  private:
+  // Only Destroy() should be deleting |this|.
+  virtual ~GpuVideoDecodeAcceleratorHost();
+
   void Send(IPC::Message* message);
 
   void OnBitstreamBufferProcessed(int32 bitstream_buffer_id);