Revert of content/common: Remove use of MessageLoopProxy and deprecated MessageLoop APIs

content/common/gpu/media/v4l2_video_decode_accelerator.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.
 //
 // This file contains an implementation of VideoDecodeAccelerator
 // that utilizes hardware video decoders, which expose Video4Linux 2 API
 // (http://linuxtv.org/downloads/v4l-dvb-apis/).
 
 #ifndef CONTENT_COMMON_GPU_MEDIA_V4L2_VIDEO_DECODE_ACCELERATOR_H_
 #define CONTENT_COMMON_GPU_MEDIA_V4L2_VIDEO_DECODE_ACCELERATOR_H_
 
 #include <queue>
 #include <vector>
 
 #include "base/callback_forward.h"
 #include "base/memory/linked_ptr.h"
 #include "base/memory/ref_counted.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/synchronization/waitable_event.h"
 #include "base/threading/thread.h"
 #include "content/common/content_export.h"
 #include "content/common/gpu/media/v4l2_device.h"
 #include "media/base/limits.h"
 #include "media/base/video_decoder_config.h"
 #include "media/video/picture.h"
 #include "media/video/video_decode_accelerator.h"
 #include "ui/gfx/geometry/size.h"
 #include "ui/gl/gl_bindings.h"
 
+namespace base {
+class MessageLoopProxy;
+}  // namespace base
+
 namespace media {
 class H264Parser;
 }  // namespace media
 
 namespace content {
 // This class handles video accelerators directly through a V4L2 device exported
 // by the hardware blocks.
 //
 // The threading model of this class is driven by the fact that it needs to
 // interface two fundamentally different event queues -- the one Chromium
@@ skipping 31 matching lines @@
 // thread while we wait for AssignPictureBuffers from the client.
 class CONTENT_EXPORT V4L2VideoDecodeAccelerator
     : public media::VideoDecodeAccelerator {
  public:
   V4L2VideoDecodeAccelerator(
       EGLDisplay egl_display,
       EGLContext egl_context,
       const base::WeakPtr<Client>& io_client_,
       const base::Callback<bool(void)>& make_context_current,
       const scoped_refptr<V4L2Device>& device,
-      const scoped_refptr<base::SingleThreadTaskRunner>& io_task_runner);
+      const scoped_refptr<base::MessageLoopProxy>& io_message_loop_proxy);
   ~V4L2VideoDecodeAccelerator() override;
 
   // media::VideoDecodeAccelerator implementation.
   // Note: Initialize() and Destroy() are synchronous.
   bool Initialize(media::VideoCodecProfile profile,
                   Client* client) override;
   void Decode(const media::BitstreamBuffer& bitstream_buffer) override;
   void AssignPictureBuffers(
       const std::vector<media::PictureBuffer>& buffers) override;
   void ReusePictureBuffer(int32 picture_buffer_id) override;
@@ skipping 212 matching lines @@
 
   // Callback that indicates a picture has been cleared.
   void PictureCleared();
 
   // This method determines whether a resolution change event processing
   // is indeed required by returning true iff:
   // - width or height of the new format is different than previous format; or
   // - V4L2_CID_MIN_BUFFERS_FOR_CAPTURE has changed.
   bool IsResolutionChangeNecessary();
 
-  // Our original calling task runner for the child thread.
-  scoped_refptr<base::SingleThreadTaskRunner> child_task_runner_;
+  // Our original calling message loop for the child thread.
+  scoped_refptr<base::MessageLoopProxy> child_message_loop_proxy_;
 
-  // Task runner of the IO thread.
-  scoped_refptr<base::SingleThreadTaskRunner> io_task_runner_;
+  // Message loop of the IO thread.
+  scoped_refptr<base::MessageLoopProxy> io_message_loop_proxy_;
 
   // WeakPtr<> pointing to |this| for use in posting tasks from the decoder or
   // device worker threads back to the child thread.  Because the worker threads
   // are members of this class, any task running on those threads is guaranteed
   // that this object is still alive.  As a result, tasks posted from the child
   // thread to the decoder or device thread should use base::Unretained(this),
   // and tasks posted the other way should use |weak_this_|.
   base::WeakPtr<V4L2VideoDecodeAccelerator> weak_this_;
 
   // To expose client callbacks from VideoDecodeAccelerator.
   // NOTE: all calls to these objects *MUST* be executed on
-  // child_task_runner_.
+  // child_message_loop_proxy_.
   scoped_ptr<base::WeakPtrFactory<Client> > client_ptr_factory_;
   base::WeakPtr<Client> client_;
-  // Callbacks to |io_client_| must be executed on |io_task_runner_|.
+  // Callbacks to |io_client_| must be executed on |io_message_loop_proxy_|.
   base::WeakPtr<Client> io_client_;
 
   //
   // Decoder state, owned and operated by decoder_thread_.
   // Before decoder_thread_ has started, the decoder state is managed by
   // the child (main) thread.  After decoder_thread_ has started, the decoder
   // thread should be the only one managing these.
   //
 
   // This thread services tasks posted from the VDA API entry points by the
@@ skipping 109 matching lines @@
 
   // The WeakPtrFactory for |weak_this_|.
   base::WeakPtrFactory<V4L2VideoDecodeAccelerator> weak_this_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(V4L2VideoDecodeAccelerator);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_COMMON_GPU_MEDIA_V4L2_VIDEO_DECODE_ACCELERATOR_H_