MediaStream audio: Refactor 3 separate "glue" implementations into one.

content/renderer/media/webrtc_audio_device_impl.cc

Index: content/renderer/media/webrtc_audio_device_impl.cc
diff --git a/content/renderer/media/webrtc_audio_device_impl.cc b/content/renderer/media/webrtc_audio_device_impl.cc
index 206672d4c00f40b1b2302bf2510fb5c8d13cacec..13ac4e385459fa78f40a4e735a4858a72b9259bd 100644
--- a/content/renderer/media/webrtc_audio_device_impl.cc
+++ b/content/renderer/media/webrtc_audio_device_impl.cc
@@ -4,16 +4,14 @@
 
 #include "content/renderer/media/webrtc_audio_device_impl.h"
 
-#include "base/bind.h"
 #include "base/metrics/histogram.h"
 #include "base/strings/string_util.h"
 #include "base/win/windows_version.h"
-#include "content/renderer/media/media_stream_audio_processor.h"
-#include "content/renderer/media/webrtc_audio_capturer.h"
+#include "content/renderer/media/webrtc/processed_local_audio_source.h"
 #include "content/renderer/media/webrtc_audio_renderer.h"
-#include "content/renderer/render_thread_impl.h"
 #include "media/audio/audio_parameters.h"
 #include "media/audio/sample_rates.h"
+#include "media/base/audio_bus.h"
 
 using media::AudioParameters;
 using media::ChannelLayout;
@@ -360,7 +358,7 @@ int32_t WebRtcAudioDeviceImpl::RecordingDelay(uint16_t* delay_ms) const {
   DCHECK(signaling_thread_checker_.CalledOnValidThread());
 
   // There is no way to report a correct delay value to WebRTC since there
-  // might be multiple WebRtcAudioCapturer instances.
+  // might be multiple ProcessedLocalAudioSource instances.
   NOTREACHED();
   return -1;
 }
@@ -421,7 +419,8 @@ bool WebRtcAudioDeviceImpl::SetAudioRenderer(WebRtcAudioRenderer* renderer) {
   return true;
 }
 
-void WebRtcAudioDeviceImpl::AddAudioCapturer(WebRtcAudioCapturer* capturer) {
+void WebRtcAudioDeviceImpl::AddAudioCapturer(
+    ProcessedLocalAudioSource* capturer) {
   DCHECK(main_thread_checker_.CalledOnValidThread());
   DVLOG(1) << "WebRtcAudioDeviceImpl::AddAudioCapturer()";
   DCHECK(capturer);
@@ -433,7 +432,8 @@ void WebRtcAudioDeviceImpl::AddAudioCapturer(WebRtcAudioCapturer* capturer) {
   capturers_.push_back(capturer);
 }
 
-void WebRtcAudioDeviceImpl::RemoveAudioCapturer(WebRtcAudioCapturer* capturer) {
+void WebRtcAudioDeviceImpl::RemoveAudioCapturer(
+    ProcessedLocalAudioSource* capturer) {
   DCHECK(main_thread_checker_.CalledOnValidThread());
   DVLOG(1) << "WebRtcAudioDeviceImpl::RemoveAudioCapturer()";
   DCHECK(capturer);