[chromecast] Bind and run mojo media services on cma thread.

media/mojo/services/mojo_media_client.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.
 
 #ifndef MEDIA_MOJO_SERVICES_MOJO_MEDIA_CLIENT_H_
 #define MEDIA_MOJO_SERVICES_MOJO_MEDIA_CLIENT_H_
 
 #include "media/base/audio_decoder.h"
 #include "media/base/audio_renderer_sink.h"
 #include "media/base/cdm_factory.h"
@@ skipping 37 matching lines @@
   // CreateRendererFactory(). May be null if the RendererFactory doesn't need an
   // audio or video sink. If not null, the sink must be owned by the client.
   virtual AudioRendererSink* CreateAudioRendererSink();
   virtual VideoRendererSink* CreateVideoRendererSink(
       const scoped_refptr<base::SingleThreadTaskRunner>& task_runner);
 
   // Returns the CdmFactory to be used by MojoCdmService.
   virtual scoped_ptr<CdmFactory> CreateCdmFactory(
       mojo::shell::mojom::InterfaceProvider* interface_provider);
 
+  // Returns the task runner to run media tasks.
+  // If it returns NULL, a default task runner will be used.
+  base::SingleThreadTaskRunner* media_task_runner() const {
+    return media_task_runner_.get();
+  }
+
  protected:
-  MojoMediaClient();
+  MojoMediaClient(
+      scoped_refptr<base::SingleThreadTaskRunner> media_task_runner);
+
+ private:
+  const scoped_refptr<base::SingleThreadTaskRunner> media_task_runner_;
 };
 
 }  // namespace media
 
 #endif  // MEDIA_MOJO_SERVICES_MOJO_MEDIA_CLIENT_H_