Add vector_math::FMUL. Replace audio_util::AdjustVolume.

media/base/audio_bus.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_BUS_H_
 #define MEDIA_BASE_AUDIO_BUS_H_
 
 #include <vector>
 
 #include "base/memory/aligned_memory.h"
@@ skipping 74 matching lines @@
 
   int channels() const { return static_cast<int>(channel_data_.size()); }
   int frames() const { return frames_; }
   void set_frames(int frames);
 
   // Helper method for zeroing out all channels of audio data.
   void Zero();
   void ZeroFrames(int frames);
   void ZeroFramesPartial(int start_frame, int frames);
 
+  // Scale internal channel values by |volume| >= 0.  If an invalid value
+  // is provided, no adjustment is done.
+  void Scale(float volume);
+
  private:
   friend struct base::DefaultDeleter<AudioBus>;
   ~AudioBus();
 
   AudioBus(int channels, int frames);
   AudioBus(int channels, int frames, float* data);
   AudioBus(int frames, const std::vector<float*>& channel_data);
   explicit AudioBus(int channels);
 
   // Helper method for building |channel_data_| from a block of memory.  |data|
   // must be at least BlockSize() bytes in size.
   void BuildChannelData(int channels, int aligned_frame, float* data);
 
   // Contiguous block of channel memory.
   scoped_ptr_malloc<float, base::ScopedPtrAlignedFree> data_;
 
   std::vector<float*> channel_data_;
   int frames_;
 
   // Protect SetChannelData() and set_frames() for use by CreateWrapper().
   bool can_set_channel_data_;
 
   DISALLOW_COPY_AND_ASSIGN(AudioBus);
 };
 
 }  // namespace media
 
 #endif  // MEDIA_BASE_AUDIO_BUS_H_