Express audio delay more precisely in frames rather than milliseconds.

media/audio/audio_device_thread.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_AUDIO_AUDIO_DEVICE_THREAD_H_
 #define MEDIA_AUDIO_AUDIO_DEVICE_THREAD_H_
 
 #include <stdint.h>
 
 #include "base/macros.h"
@@ skipping 42 matching lines @@
     virtual void MapSharedMemory() = 0;
 
     // Called whenever we receive notifications about pending input data.
     virtual void Process(uint32_t pending_data) = 0;
 
    protected:
     // Protected so that derived classes can access directly.
     // The variables are 'const' since values are calculated/set in the
     // constructor and must never change.
     const AudioParameters audio_parameters_;
-    const int samples_per_ms_;
-    const int bytes_per_ms_;
+    const double samples_per_ms_;
+    const double bytes_per_ms_;
+    const uint32_t bytes_per_frame_;
 
     base::SharedMemory shared_memory_;
     const int memory_length_;
     const int total_segments_;
     int segment_length_;
 
    private:
     DISALLOW_COPY_AND_ASSIGN(Callback);
   };
 
@@ skipping 34 matching lines @@
 
   base::Lock thread_lock_;
   scoped_refptr<AudioDeviceThread::Thread> thread_;
 
   DISALLOW_COPY_AND_ASSIGN(AudioDeviceThread);
 };
 
 }  // namespace media.
 
 #endif  // MEDIA_AUDIO_AUDIO_DEVICE_THREAD_H_