Convert media constants to constexpr.

media/base/audio_timestamp_helper.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_AUDIO_TIMESTAMP_HELPER_H_
 #define MEDIA_BASE_AUDIO_TIMESTAMP_HELPER_H_
 
 #include <stdint.h>
 
 #include "base/macros.h"
@@ skipping 22 matching lines @@
   explicit AudioTimestampHelper(int samples_per_second);
 
   // Sets the base timestamp to |base_timestamp| and the sets count to 0.
   void SetBaseTimestamp(base::TimeDelta base_timestamp);
 
   base::TimeDelta base_timestamp() const;
   int64_t frame_count() const { return frame_count_; }
 
   // Adds |frame_count| to the frame counter.
   // Note: SetBaseTimestamp() must be called with a value other than
-  // kNoTimestamp() before this method can be called.
+  // kNoTimestamp before this method can be called.
   void AddFrames(int frame_count);
 
   // Get the current timestamp. This value is computed from the base_timestamp()
   // and the number of sample frames that have been added so far.
   base::TimeDelta GetTimestamp() const;
 
   // Gets the duration if |frame_count| frames were added to the current
   // timestamp reported by GetTimestamp(). This method ensures that
   // (GetTimestamp() + GetFrameDuration(n)) will equal the timestamp that
   // GetTimestamp() will return if AddFrames(n) is called.
@@ skipping 12 matching lines @@
 
   // Number of frames accumulated by AddFrames() calls.
   int64_t frame_count_;
 
   DISALLOW_IMPLICIT_CONSTRUCTORS(AudioTimestampHelper);
 };
 
 }  // namespace media
 
 #endif  // MEDIA_BASE_AUDIO_TIMESTAMP_HELPER_H_