Reland: Use a shared thread for media operations (round 3).

webkit/renderer/media/webmediaplayer_params.h

 // Copyright 2013 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 WEBKIT_RENDERER_MEDIA_WEBMEDIAPLAYER_PARAMS_H_
 #define WEBKIT_RENDERER_MEDIA_WEBMEDIAPLAYER_PARAMS_H_
 
 #include "base/memory/ref_counted.h"
 #include "media/filters/gpu_video_decoder.h"
 
+namespace base {
+class MessageLoopProxy;
+}
+
 namespace media {
 class AudioRendererSink;
 class MediaLog;
 }
 
 namespace webkit_media {
 
 // Holds parameters for constructing WebMediaPlayerImpl without having
 // to plumb arguments through various abstraction layers.
 class WebMediaPlayerParams {
  public:
-  // |media_log| is the only required parameter; all others may be null.
+  // |message_loop_proxy| and |media_log| are the only required parameters;
+  // all others may be null.
   WebMediaPlayerParams(
+      const scoped_refptr<base::MessageLoopProxy>& message_loop_proxy,
       const scoped_refptr<media::AudioRendererSink>& audio_renderer_sink,
       const scoped_refptr<media::GpuVideoDecoder::Factories>& gpu_factories,
       const scoped_refptr<media::MediaLog>& media_log);
   ~WebMediaPlayerParams();
 
+  const scoped_refptr<base::MessageLoopProxy>& message_loop_proxy() const {
+    return message_loop_proxy_;
+  }
+
   const scoped_refptr<media::AudioRendererSink>& audio_renderer_sink() const {
     return audio_renderer_sink_;
   }
 
   const scoped_refptr<media::GpuVideoDecoder::Factories>&
   gpu_factories() const {
     return gpu_factories_;
   }
 
   const scoped_refptr<media::MediaLog>& media_log() const {
     return media_log_;
   }
 
  private:
+  scoped_refptr<base::MessageLoopProxy> message_loop_proxy_;
   scoped_refptr<media::AudioRendererSink> audio_renderer_sink_;
   scoped_refptr<media::GpuVideoDecoder::Factories> gpu_factories_;
   scoped_refptr<media::MediaLog> media_log_;
 
   DISALLOW_IMPLICIT_CONSTRUCTORS(WebMediaPlayerParams);
 };
 
 }  // namespace media
 
 #endif  // WEBKIT_RENDERER_MEDIA_WEBMEDIAPLAYER_PARAMS_H_