[Chromecast] Upgrade to new CMA backend API

chromecast/public/media/media_pipeline_device_params.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 CHROMECAST_PUBLIC_MEDIA_MEDIA_PIPELINE_DEVICE_PARAMS_H_
 #define CHROMECAST_PUBLIC_MEDIA_MEDIA_PIPELINE_DEVICE_PARAMS_H_
 
-#include "task_runner.h"
+namespace chromecast {
+class TaskRunner;
 
-namespace chromecast {
 namespace media {
 
 // Supplies creation parameters to platform-specific pipeline backend.
 struct MediaPipelineDeviceParams {
   enum MediaSyncType {
     // Default operation, synchronize playback using PTS with higher latency.
     kModeSyncPts = 0,
     // With this mode, synchronization is disabled and audio/video frames are
     // rendered "right away":
     // - for audio, frames are still rendered based on the sampling frequency
@@ skipping 19 matching lines @@
   // thread.  Since all calls from cast_shell into the backend are made on
   // the media thread, this may simplify thread management and safety for
   // some backends.
   TaskRunner* const task_runner;
 };
 
 }  // namespace media
 }  // namespace chromecast
 
 #endif  // CHROMECAST_MEDIA_CMA_BACKEND_MEDIA_PIPELINE_DEVICE_PARAMS_H_