Clean up audio-related utility functions to compute buffer sizes

media/audio/audio_parameters.h

 // Copyright (c) 2011 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_PARAMETERS_H_
 #define MEDIA_AUDIO_AUDIO_PARAMETERS_H_
 
 #include "base/basictypes.h"
 #include "media/base/channel_layout.h"
 #include "media/base/media_export.h"
 
+// TODO(vrk): This should probably be changed to an immutable object instead of
+// a struct. See crbug.com/115902.
 struct MEDIA_EXPORT AudioParameters {
   // Compare is useful when AudioParameters is used as a key in std::map.
   class MEDIA_EXPORT Compare {
    public:
     bool operator()(const AudioParameters& a, const AudioParameters& b) const;
   };
 
   enum Format {
     AUDIO_PCM_LINEAR = 0,     // PCM is 'raw' amplitude samples.
     AUDIO_PCM_LOW_LATENCY,    // Linear PCM, low latency requested.
@@ skipping 26 matching lines @@
   ChannelLayout channel_layout;  // Order of surround sound channels.
   int sample_rate;               // Sampling frequency/rate.
   int bits_per_sample;           // Number of bits per sample.
   int samples_per_packet;        // Size of a packet in frames.
 
   int channels;                  // Number of channels. Value set based on
                                  // |channel_layout|.
 };
 
 #endif  // MEDIA_AUDIO_AUDIO_PARAMETERS_H_