Extract media::Clock::IsPlaying() into media::Pipeline::ClockState enum.

media/base/pipeline.h

 // Copyright (c) 2012 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_BASE_PIPELINE_H_
 #define MEDIA_BASE_PIPELINE_H_
 
 #include <string>
 
 #include "base/gtest_prod_util.h"
@@ skipping 308 matching lines @@
   //   - A waiting to non-waiting transition indicates preroll has completed
   //     and StartPlayback() should be called
   //   - A non-waiting to waiting transition indicates underflow has occurred
   //     and StartWaitingForEnoughData() should be called
   void BufferingStateChanged(BufferingState* buffering_state,
                              BufferingState new_buffering_state);
   bool WaitingForEnoughData() const;
   void StartWaitingForEnoughData();
   void StartPlayback();
 
+  void PauseClockAndStopRendering_Locked();
   void StartClockIfWaitingForTimeUpdate_Locked();
 
   // Task runner used to execute pipeline tasks.
   scoped_refptr<base::SingleThreadTaskRunner> task_runner_;
 
   // MediaLog to which to log events.
   scoped_refptr<MediaLog> media_log_;
 
   // Lock used to serialize access for the following data members.
   mutable base::Lock lock_;
@@ skipping 19 matching lines @@
   float playback_rate_;
 
   // base::TickClock used by |clock_|.
   base::DefaultTickClock default_tick_clock_;
 
   // Reference clock.  Keeps track of current playback time.  Uses system
   // clock and linear interpolation, but can have its time manually set
   // by filters.
   scoped_ptr<Clock> clock_;
 
-  // If this value is set to true, then |clock_| is paused and we are waiting
-  // for an update of the clock greater than or equal to the elapsed time to
-  // start the clock.
-  bool waiting_for_clock_update_;
+  enum ClockState {
+    // Audio (if present) is not rendering. Clock isn't playing.
+    CLOCK_PAUSED,
+
+    // Audio (if present) is rendering. Clock isn't playing.
+    CLOCK_WAITING_FOR_AUDIO_TIME_UPDATE,
+
+    // Audio (if present) is rendering. Clock is playing.
+    CLOCK_PLAYING,
+  };
+
+  ClockState clock_state_;
 
   // Status of the pipeline.  Initialized to PIPELINE_OK which indicates that
   // the pipeline is operating correctly. Any other value indicates that the
   // pipeline is stopped or is stopping.  Clients can call the Stop() method to
   // reset the pipeline state, and restore this to PIPELINE_OK.
   PipelineStatus status_;
 
   // The following data members are only accessed by tasks posted to
   // |task_runner_|.
 
@@ skipping 42 matching lines @@
   scoped_ptr<SerialRunner> pending_callbacks_;
 
   base::ThreadChecker thread_checker_;
 
   DISALLOW_COPY_AND_ASSIGN(Pipeline);
 };
 
 }  // namespace media
 
 #endif  // MEDIA_BASE_PIPELINE_H_