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

media/audio/audio_output_resampler.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_output_resampler.h"
 
 #include "base/bind.h"
 #include "base/bind_helpers.h"
 #include "base/compiler_specific.h"
 #include "base/message_loop.h"
@@ skipping 123 matching lines @@
   }
 
   // TODO(dalecurtis): All this code should be merged into AudioOutputMixer once
   // we've stabilized the issues there.
   dispatcher_ = new AudioOutputDispatcherImpl(
       audio_manager_, output_params_, close_delay_);
 }
 
 bool AudioOutputResampler::OpenStream() {
   if (dispatcher_->OpenStream()) {
-    UMA_HISTOGRAM_BOOLEAN("Media.FallbackToHighLatencyAudioPath", false);
+    if (output_params_.format() == AudioParameters::AUDIO_PCM_LOW_LATENCY)
+      UMA_HISTOGRAM_BOOLEAN("Media.FallbackToHighLatencyAudioPath", false);
     return true;
   }
 
   // If we've already tried to open the stream in high latency mode, there's
   // nothing more to be done.
   if (output_params_.format() == AudioParameters::AUDIO_PCM_LINEAR)
     return false;
 
   DLOG(ERROR) << "Unable to open audio device in low latency mode.  Falling "
               << "back to high latency audio output.";
@@ skipping 137 matching lines @@
     source_callback_->OnError(stream, code);
 }
 
 void AudioOutputResampler::WaitTillDataReady() {
   base::AutoLock auto_lock(source_lock_);
   if (source_callback_ && !outstanding_audio_bytes_)
     source_callback_->WaitTillDataReady();
 }
 
 }  // namespace media