Made AudioReceiveStream a mixer participant.

webrtc/voice_engine/channel_proxy.h

Index: webrtc/voice_engine/channel_proxy.h
diff --git a/webrtc/voice_engine/channel_proxy.h b/webrtc/voice_engine/channel_proxy.h
index d84e73b60f605d513e7dd5fc9cc91d48174523cb..05999ec8a13d7a8d783c014278868d9f9db514fd 100644
--- a/webrtc/voice_engine/channel_proxy.h
+++ b/webrtc/voice_engine/channel_proxy.h
@@ -15,6 +15,7 @@
 #include "webrtc/base/thread_checker.h"
 #include "webrtc/voice_engine/channel_manager.h"
 #include "webrtc/voice_engine/include/voe_rtp_rtcp.h"
+#include "webrtc/modules/audio_mixer/audio_mixer_defines.h"
 
 #include <memory>
 #include <string>
@@ -91,6 +92,10 @@ class ChannelProxy {
 
   virtual void SetRtcEventLog(RtcEventLog* event_log);
 
+  virtual MixerAudioSource::AudioFrameWithMuted GetAudioFrameWithMuted(
+      int32_t id,
+      int sample_rate_hz);
+
  private:
   Channel* channel() const;