Allow audio system to handle synchronized low-latency audio I/O

media/audio/audio_input_device.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_input_device.h"
 
 #include "base/bind.h"
 #include "base/message_loop.h"
 #include "base/threading/thread_restrictions.h"
 #include "base/time.h"
@@ skipping 288 matching lines @@
   LOG(ERROR) << "IO loop going away before the input device has been stopped";
   ShutDownOnIOThread();
 }
 
 // AudioInputDevice::AudioThreadCallback
 AudioInputDevice::AudioThreadCallback::AudioThreadCallback(
     const AudioParameters& audio_parameters,
     base::SharedMemoryHandle memory,
     int memory_length,
     CaptureCallback* capture_callback)
-    : AudioDeviceThread::Callback(audio_parameters, memory, memory_length),
+    : AudioDeviceThread::Callback(audio_parameters, 0, memory, memory_length),
       capture_callback_(capture_callback) {
   audio_bus_ = AudioBus::Create(audio_parameters_);
 }
 
 AudioInputDevice::AudioThreadCallback::~AudioThreadCallback() {
 }
 
 void AudioInputDevice::AudioThreadCallback::MapSharedMemory() {
   shared_memory_.Map(memory_length_);
 }
@@ skipping 16 matching lines @@
   // with nominal range -1.0 -> +1.0.
   audio_bus_->FromInterleaved(memory, audio_bus_->frames(), bytes_per_sample);
 
   // Deliver captured data to the client in floating point format
   // and update the audio-delay measurement.
   capture_callback_->Capture(audio_bus_.get(),
                              audio_delay_milliseconds, volume);
 }
 
 }  // namespace media