Support external audio mixer.

webrtc/media/engine/webrtcmediaengine.cc

 /*
  *  Copyright (c) 2014 The WebRTC project authors. All Rights Reserved.
  *
  *  Use of this source code is governed by a BSD-style license
  *  that can be found in the LICENSE file in the root of the source
  *  tree. An additional intellectual property rights grant can be found
  *  in the file PATENTS.  All contributing project authors may
  *  be found in the AUTHORS file in the root of the source tree.
  */
 
@@ skipping 15 matching lines @@
 #ifdef HAVE_WEBRTC_VIDEO
     : public CompositeMediaEngine<WebRtcVoiceEngine, WebRtcVideoEngine2> {
 #else
     : public CompositeMediaEngine<WebRtcVoiceEngine, NullWebRtcVideoEngine> {
 #endif
  public:
   WebRtcMediaEngine2(webrtc::AudioDeviceModule* adm,
                      const rtc::scoped_refptr<webrtc::AudioDecoderFactory>&
                          audio_decoder_factory,
                      WebRtcVideoEncoderFactory* video_encoder_factory,
-                     WebRtcVideoDecoderFactory* video_decoder_factory)
+                     WebRtcVideoDecoderFactory* video_decoder_factory,
+                     rtc::scoped_refptr<webrtc::AudioMixer> audio_mixer)
 #ifdef HAVE_WEBRTC_VIDEO
       : CompositeMediaEngine<WebRtcVoiceEngine, WebRtcVideoEngine2>(
-            adm, audio_decoder_factory){
+            adm,
+            audio_decoder_factory,
+            audio_mixer){
 #else
       : CompositeMediaEngine<WebRtcVoiceEngine, NullWebRtcVideoEngine>(
-            adm, audio_decoder_factory) {
+            adm,
+            audio_decoder_factory,
+            audio_mixer) {
 #endif
     video_.SetExternalDecoderFactory(video_decoder_factory);
     video_.SetExternalEncoderFactory(video_encoder_factory);
   }
 };
 
 }  // namespace cricket
 
 cricket::MediaEngineInterface* CreateWebRtcMediaEngine(
     webrtc::AudioDeviceModule* adm,
     const rtc::scoped_refptr<webrtc::AudioDecoderFactory>&
         audio_decoder_factory,
     cricket::WebRtcVideoEncoderFactory* video_encoder_factory,
-    cricket::WebRtcVideoDecoderFactory* video_decoder_factory) {
-  return new cricket::WebRtcMediaEngine2(
-      adm, audio_decoder_factory, video_encoder_factory, video_decoder_factory);
+    cricket::WebRtcVideoDecoderFactory* video_decoder_factory,
+    rtc::scoped_refptr<webrtc::AudioMixer> audio_mixer) {
+  return new cricket::WebRtcMediaEngine2(adm, audio_decoder_factory,
+                                         video_encoder_factory,
+                                         video_decoder_factory, audio_mixer);
 }
 
 void DestroyWebRtcMediaEngine(cricket::MediaEngineInterface* media_engine) {
   delete media_engine;
 }
 
 namespace cricket {
 
 // TODO(ossu): Backwards-compatible interface. Will be deprecated once the
 // audio decoder factory is fully plumbed and used throughout WebRTC.
 // See: crbug.com/webrtc/6000
 MediaEngineInterface* WebRtcMediaEngineFactory::Create(
     webrtc::AudioDeviceModule* adm,
     WebRtcVideoEncoderFactory* video_encoder_factory,
-    WebRtcVideoDecoderFactory* video_decoder_factory) {
-  return CreateWebRtcMediaEngine(adm,
-                                 webrtc::CreateBuiltinAudioDecoderFactory(),
-                                 video_encoder_factory, video_decoder_factory);
+    WebRtcVideoDecoderFactory* video_decoder_factory,
+    rtc::scoped_refptr<webrtc::AudioMixer> audio_mixer) {
+  return CreateWebRtcMediaEngine(
+      adm, webrtc::CreateBuiltinAudioDecoderFactory(), video_encoder_factory,

[the sun, 2016/12/07 15:56:08]

nit: git cl format, or manually stick to one way of indenting please

[GeorgeZ, 2016/12/07 18:28:17]

I verified that this was adjusted by git cl format. Maybe git cl format doesn't
behave well for this case.

+      video_decoder_factory, audio_mixer);
 }
 
 // Used by PeerConnectionFactory to create a media engine passed into
 // ChannelManager.
 MediaEngineInterface* WebRtcMediaEngineFactory::Create(
     webrtc::AudioDeviceModule* adm,
     const rtc::scoped_refptr<webrtc::AudioDecoderFactory>&
         audio_decoder_factory,
     WebRtcVideoEncoderFactory* video_encoder_factory,
-    WebRtcVideoDecoderFactory* video_decoder_factory) {
+    WebRtcVideoDecoderFactory* video_decoder_factory,
+    rtc::scoped_refptr<webrtc::AudioMixer> audio_mixer) {
   return CreateWebRtcMediaEngine(adm, audio_decoder_factory,
-                                 video_encoder_factory, video_decoder_factory);
+                                 video_encoder_factory, video_decoder_factory,
+                                 audio_mixer);
 }
 
 namespace {
 // Remove mutually exclusive extensions with lower priority.
 void DiscardRedundantExtensions(
     std::vector<webrtc::RtpExtension>* extensions,
     rtc::ArrayView<const char*> extensions_decreasing_prio) {
   RTC_DCHECK(extensions);
   bool found = false;
   for (const char* uri : extensions_decreasing_prio) {
@@ skipping 63 matching lines @@
     static const char* kBweExtensionPriorities[] = {
         webrtc::RtpExtension::kTransportSequenceNumberUri,
         webrtc::RtpExtension::kAbsSendTimeUri,
         webrtc::RtpExtension::kTimestampOffsetUri};
     DiscardRedundantExtensions(&result, kBweExtensionPriorities);
   }
 
   return result;
 }
 }  // namespace cricket