Reland: Remove reference counting from media::VideoDecoder and friends.

media/filters/gpu_video_decoder.h

 // Copyright (c) 2012 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 MEDIA_FILTERS_GPU_VIDEO_DECODER_H_
 #define MEDIA_FILTERS_GPU_VIDEO_DECODER_H_
 
 #include <list>
 #include <map>
 #include <utility>
 #include <vector>
 
+#include "base/memory/weak_ptr.h"
 #include "media/base/pipeline_status.h"
 #include "media/base/demuxer_stream.h"
 #include "media/base/video_decoder.h"
 #include "media/video/video_decode_accelerator.h"
 
 template <class T> class scoped_refptr;
 
 namespace base {
 class MessageLoopProxy;
 class SharedMemory;
 }
 
 class SkBitmap;
 
 namespace media {
 
 class DecoderBuffer;
+class VDAClientProxy;
 
 // GPU-accelerated video decoder implementation.  Relies on
 // AcceleratedVideoDecoderMsg_Decode and friends.
 // All methods internally trampoline to the |message_loop| passed to the ctor.
 class MEDIA_EXPORT GpuVideoDecoder
     : public VideoDecoder,
       public VideoDecodeAccelerator::Client {
  public:
   // Helper interface for specifying factories needed to instantiate a
   // GpuVideoDecoder.
@@ skipping 17 matching lines @@
     // Close()ing the returned pointer.
     virtual base::SharedMemory* CreateSharedMemory(size_t size) = 0;
 
     // Returns the message loop the VideoDecodeAccelerator runs on.
     virtual scoped_refptr<base::MessageLoopProxy> GetMessageLoop() = 0;
 
     // Abort any outstanding factory operations and error any future
     // attempts at factory operations
     virtual void Abort() = 0;
 
-    // Returns true if Abort has been called.
+    // Returns true if Abort() has been called.
     virtual bool IsAborted() = 0;
 
    protected:
     friend class base::RefCountedThreadSafe<Factories>;
     virtual ~Factories();
   };
 
   GpuVideoDecoder(const scoped_refptr<base::MessageLoopProxy>& message_loop,
                   const scoped_refptr<Factories>& factories);
 
@@ skipping 49 matching lines @@
       const scoped_refptr<VideoFrame>& frame);
 
   // Indicate the picture buffer can be reused by the decoder.
   void ReusePictureBuffer(int64 picture_buffer_id);
 
   void RecordBufferData(
       const BitstreamBuffer& bitstream_buffer, const DecoderBuffer& buffer);
   void GetBufferData(int32 id, base::TimeDelta* timetamp,
                      gfx::Rect* visible_rect, gfx::Size* natural_size);
 
-  // Set |vda_| and |weak_vda_| on the VDA thread (in practice the render
-  // thread).
-  void SetVDA(VideoDecodeAccelerator* vda);
+  // Sets |vda_| and |weak_vda_| on the GVD thread and runs |status_cb|.
+  void SetVDA(const PipelineStatusCB& status_cb,
+              VideoDecodeAccelerator* vda,
+              base::WeakPtr<VideoDecodeAccelerator> weak_vda);
 
   // Call VDA::Destroy() on |vda_loop_proxy_| ensuring that |this| outlives the
   // Destroy() call.
   void DestroyVDA();
 
   // A shared memory segment and its allocated size.
   struct SHMBuffer {
     SHMBuffer(base::SharedMemory* m, size_t s);
     ~SHMBuffer();
     base::SharedMemory* shm;
@@ skipping 10 matching lines @@
   void DestroyTextures();
 
   StatisticsCB statistics_cb_;
 
   // Pointer to the demuxer stream that will feed us compressed buffers.
   scoped_refptr<DemuxerStream> demuxer_stream_;
 
   // MessageLoop on which to fire callbacks and trampoline calls to this class
   // if they arrive on other loops.
   scoped_refptr<base::MessageLoopProxy> gvd_loop_proxy_;
+  base::WeakPtrFactory<GpuVideoDecoder> weak_factory_;
+  base::WeakPtr<GpuVideoDecoder> weak_this_;
 
   // Message loop on which to makes all calls to vda_.  (beware this loop may be
   // paused during the Pause/Flush/Stop dance PipelineImpl::Stop() goes
   // through).
   scoped_refptr<base::MessageLoopProxy> vda_loop_proxy_;
 
   scoped_refptr<Factories> factories_;
 
+  // Proxies calls from |vda_| to |gvd_loop_proxy_| and used to safely detach
+  // during shutdown.
+  scoped_refptr<VDAClientProxy> client_proxy_;
+
   // Populated during Initialize() via SetVDA() (on success) and unchanged
-  // until an error occurs
+  // until an error occurs.
   scoped_ptr<VideoDecodeAccelerator> vda_;
   // Used to post tasks from the GVD thread to the VDA thread safely.
   base::WeakPtr<VideoDecodeAccelerator> weak_vda_;
 
   // Callbacks that are !is_null() only during their respective operation being
   // asynchronously executed.
   ReadCB pending_read_cb_;
   base::Closure pending_reset_cb_;
 
   State state_;
@@ skipping 42 matching lines @@
   // Set during ProvidePictureBuffers(), used for checking and implementing
   // HasAvailableOutputFrames().
   int available_pictures_;
 
   DISALLOW_COPY_AND_ASSIGN(GpuVideoDecoder);
 };
 
 }  // namespace media
 
 #endif  // MEDIA_FILTERS_GPU_VIDEO_DECODER_H_