Add support for channel transforms.

media/audio/pulse/pulse_output.cc

 // 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.
 
 #include "media/audio/pulse/pulse_output.h"
 
 #include "base/bind.h"
 #include "base/message_loop.h"
 #include "media/audio/audio_parameters.h"
 #include "media/audio/audio_util.h"
@@ skipping 30 matching lines @@
     default:
       return PA_SAMPLE_INVALID;
   }
 }
 
 static pa_channel_position ChromiumToPAChannelPosition(Channels channel) {
   switch (channel) {
     // PulseAudio does not differentiate between left/right and
     // stereo-left/stereo-right, both translate to front-left/front-right.
     case LEFT:
-    case STEREO_LEFT:
       return PA_CHANNEL_POSITION_FRONT_LEFT;
     case RIGHT:
-    case STEREO_RIGHT:
       return PA_CHANNEL_POSITION_FRONT_RIGHT;
     case CENTER:
       return PA_CHANNEL_POSITION_FRONT_CENTER;
     case LFE:
       return PA_CHANNEL_POSITION_LFE;
     case BACK_LEFT:
       return PA_CHANNEL_POSITION_REAR_LEFT;
     case BACK_RIGHT:
       return PA_CHANNEL_POSITION_REAR_RIGHT;
     case LEFT_OF_CENTER:
@@ skipping 364 matching lines @@
 
 int PulseAudioOutputStream::RunDataCallback(
     AudioBus* audio_bus, AudioBuffersState buffers_state) {
   if (source_callback_)
     return source_callback_->OnMoreData(audio_bus, buffers_state);
 
   return 0;
 }
 
 }  // namespace media