[Chromecast] Upgrade to new CMA backend API

chromecast/media/cma/adapter/media_pipeline_backend_v1.h

 // Copyright 2015 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 CHROMECAST_PUBLIC_MEDIA_MEDIA_PIPELINE_BACKEND_H_
-#define CHROMECAST_PUBLIC_MEDIA_MEDIA_PIPELINE_BACKEND_H_
+#ifndef CHROMECAST_MEDIA_CMA_ADAPTER_MEDIA_PIPELINE_BACKEND_V1_H_
+#define CHROMECAST_MEDIA_CMA_ADAPTER_MEDIA_PIPELINE_BACKEND_V1_H_
 
 namespace chromecast {
 namespace media {
 
 class AudioPipelineDevice;
 class MediaClockDevice;
 struct MediaPipelineDeviceParams;
 class VideoPipelineDevice;
 
 // Interface for creating and managing ownership of platform-specific clock,
 // audio and video devices.  cast_shell owns the MediaPipelineBackend for
 // as long as it is needed; the implementation is responsible for
 // tearing down the individual components correctly when it is destroyed.
 // A new MediaPipelineBackend will be instantiated for each media player
 // instance.
-class MediaPipelineBackend {
+class MediaPipelineBackendV1 {
  public:
-  virtual ~MediaPipelineBackend() {}
+  virtual ~MediaPipelineBackendV1() {}
 
   // Returns the platform-specific pipeline clock.
   virtual MediaClockDevice* GetClock() = 0;
 
   // Returns the platform-specific audio backend.
   virtual AudioPipelineDevice* GetAudio() = 0;
 
   // Returns the platform-specific video backend.
   virtual VideoPipelineDevice* GetVideo() = 0;
 };
 
 }  // namespace media
 }  // namespace chromecast
 
-#endif  // CHROMECAST_MEDIA_CMA_BACKEND_MEDIA_PIPELINE_DEVICE_FACTORY_H_
+#endif  // CHROMECAST_MEDIA_CMA_ADAPTER_MEDIA_PIPELINE_BACKEND_V1_H_