Support external audio mixer.

webrtc/api/peerconnectioninterface.h

 /*
  *  Copyright 2012 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 38 matching lines @@
 // function OnIceCandidate. Send these candidates to the remote peer.
 
 #ifndef WEBRTC_API_PEERCONNECTIONINTERFACE_H_
 #define WEBRTC_API_PEERCONNECTIONINTERFACE_H_
 
 #include <memory>
 #include <string>
 #include <utility>
 #include <vector>
 
+#include "webrtc/api/audio/audio_mixer.h"
 #include "webrtc/api/datachannelinterface.h"
 #include "webrtc/api/dtmfsenderinterface.h"
 #include "webrtc/api/jsep.h"
 #include "webrtc/api/mediastreaminterface.h"
 #include "webrtc/api/rtcstatscollector.h"
 #include "webrtc/api/rtpreceiverinterface.h"
 #include "webrtc/api/rtpsenderinterface.h"
 #include "webrtc/api/statstypes.h"
 #include "webrtc/api/umametrics.h"
 #include "webrtc/base/fileutils.h"
@@ skipping 459 matching lines @@
     return false;
   }
 
   // Stops logging the RtcEventLog.
   // TODO(ivoc): Make this pure virtual when Chrome is updated.
   virtual void StopRtcEventLog() {}
 
   // Terminates all media and closes the transport.
   virtual void Close() = 0;
 
+  // Get remote audio tracks' ssrcs.
+  virtual std::vector<uint32_t> GetRemoteAudioTrackSsrcs() = 0;
+
  protected:
   // Dtor protected as objects shouldn't be deleted via this interface.
   ~PeerConnectionInterface() {}
 };
 
 // PeerConnection callback interface. Application should implement these
 // methods.
 class PeerConnectionObserver {
  public:
   enum StateType {
@@ skipping 218 matching lines @@
     rtc::Thread* worker_and_network_thread,
     rtc::Thread* signaling_thread,
     AudioDeviceModule* default_adm,
     cricket::WebRtcVideoEncoderFactory* encoder_factory,
     cricket::WebRtcVideoDecoderFactory* decoder_factory) {
   return CreatePeerConnectionFactory(
       worker_and_network_thread, worker_and_network_thread, signaling_thread,
       default_adm, encoder_factory, decoder_factory);
 }
 
+// Create a new instance of PeerConnectionFactoryInterface with external audio
+// mixer.
+//
+// |network_thread|, |worker_thread| and |signaling_thread| are
+// the only mandatory parameters.
+//
+// If non-null, ownership of |default_adm|, |encoder_factory| and
+// |decoder_factory| are transferred to the returned factory.

[aleloi, 2016/12/05 14:03:08]

The comment should mention the new argument |audio_mixed|. For the other
arguments, I don't think the same thing has to be repeated as in the first
c-tor. (So only document the difference and the new parameter). Also, I think
this should be moved above the |worker_and_network_thread|-constructor, because
it's more similar to the first c-tor 

[GeorgeZ, 2016/12/05 17:56:18]

Done.

+rtc::scoped_refptr<PeerConnectionFactoryInterface>
+CreatePeerConnectionFactoryWithAudioMixer(
+    rtc::Thread* network_thread,
+    rtc::Thread* worker_thread,
+    rtc::Thread* signaling_thread,
+    AudioDeviceModule* default_adm,
+    cricket::WebRtcVideoEncoderFactory* encoder_factory,
+    cricket::WebRtcVideoDecoderFactory* decoder_factory,
+    rtc::scoped_refptr<AudioMixer> audio_mixer);
+
 }  // namespace webrtc
 
 #endif  // WEBRTC_API_PEERCONNECTIONINTERFACE_H_