Bypass audio resampler on XP / non-WASAPI wave out path.

media/audio/audio_manager_base.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/audio_manager_base.h"
 
 #include "base/bind.h"
 #include "base/command_line.h"
 #include "base/message_loop_proxy.h"
 #include "base/threading/thread.h"
@@ skipping 142 matching lines @@
   if (it != output_dispatchers_.end())
     return new AudioOutputProxy(it->second);
 
   base::TimeDelta close_delay =
       base::TimeDelta::FromSeconds(kStreamCloseDelaySeconds);
 
   const CommandLine* cmd_line = CommandLine::ForCurrentProcess();
   if (cmd_line->HasSwitch(switches::kEnableAudioOutputResampler) &&
       params.format() == AudioParameters::AUDIO_PCM_LOW_LATENCY) {
     scoped_refptr<AudioOutputDispatcher> dispatcher = new AudioOutputResampler(
-        this, params,
-        GetPreferredLowLatencyOutputStreamParameters(params.channel_layout()),
+        this, params, GetPreferredLowLatencyOutputStreamParameters(params),
         close_delay);
     output_dispatchers_[params] = dispatcher;
     return new AudioOutputProxy(dispatcher);
   }
 
 #if defined(ENABLE_AUDIO_MIXER)
   // TODO(dalecurtis): Browser side mixing has a couple issues that must be
   // fixed before it can be turned on by default: http://crbug.com/138098 and
   // http://crbug.com/140247
   if (cmd_line->HasSwitch(switches::kEnableAudioMixer)) {
@@ skipping 97 matching lines @@
       DCHECK(dispatcher->HasOneRef()) << "AudioOutputProxies are still alive";
       dispatcher = NULL;
     }
   }
 
   output_dispatchers_.clear();
 #endif  // defined(OS_IOS)
 }
 
 AudioParameters AudioManagerBase::GetPreferredLowLatencyOutputStreamParameters(
-    ChannelLayout channel_layout) {
+    const AudioParameters& input_params) {
 #if defined(OS_IOS)
   // IOS implements audio input only.
   NOTIMPLEMENTED();
   return AudioParameters();
 #else
   // TODO(dalecurtis): This should include bits per channel and channel layout
   // eventually.
   return AudioParameters(
-      AudioParameters::AUDIO_PCM_LOW_LATENCY, channel_layout,
+      AudioParameters::AUDIO_PCM_LOW_LATENCY, input_params.channel_layout(),
       GetAudioHardwareSampleRate(), 16, GetAudioHardwareBufferSize());
 #endif  // defined(OS_IOS)
 }
 
 }  // namespace media