Move some receive stream configuration into webrtc::AudioReceiveStream.

webrtc/audio/audio_receive_stream.h

Index: webrtc/audio/audio_receive_stream.h
diff --git a/webrtc/audio/audio_receive_stream.h b/webrtc/audio/audio_receive_stream.h
index a461aadc5f58f093b532dbfac5f241452f3eb445..e7a2952a2a27db63e12555ff3e5c89294fc41f22 100644
--- a/webrtc/audio/audio_receive_stream.h
+++ b/webrtc/audio/audio_receive_stream.h
@@ -44,6 +44,8 @@ class AudioReceiveStream final : public webrtc::AudioReceiveStream {
   const webrtc::AudioReceiveStream::Config& config() const;
 
  private:
+  VoiceEngine* voice_engine() const;
+
   rtc::ThreadChecker thread_checker_;
   RemoteBitrateEstimator* const remote_bitrate_estimator_;
   const webrtc::AudioReceiveStream::Config config_;