Move the refcounting from the proxy/impl resource object to the shared resource object base class.

ppapi/shared_impl/video_decoder_impl.h

Index: ppapi/shared_impl/video_decoder_impl.h
diff --git a/ppapi/shared_impl/video_decoder_impl.h b/ppapi/shared_impl/video_decoder_impl.h
index cc0da6daed8f479fe79b91de389fcb21a7d79a55..b874bba7135e991985286a7ea7e59e25d3ccdae0 100644
--- a/ppapi/shared_impl/video_decoder_impl.h
+++ b/ppapi/shared_impl/video_decoder_impl.h
@@ -30,15 +30,11 @@ namespace ppapi {
 
 // Implements the logic to set and run callbacks for various video decoder
 // events. Both the proxy and the renderer implementation share this code.
-class VideoDecoderImpl : public ResourceObjectBase,
-                         public thunk::PPB_VideoDecoder_API {
+class VideoDecoderImpl : public thunk::PPB_VideoDecoder_API {
  public:
   VideoDecoderImpl();
   virtual ~VideoDecoderImpl();
 
-  // ResourceObjectBase implementation.
-  virtual PPB_VideoDecoder_API* AsPPB_VideoDecoder_API() OVERRIDE;
-
   // PPB_VideoDecoder_API implementation.
   virtual void Destroy() OVERRIDE;