Made AudioReceiveStream a mixer participant.

webrtc/voice_engine/channel.cc

 /*
  *  Copyright (c) 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 677 matching lines @@
         capture_start_ntp_time_ms_ =
             audioFrame->ntp_time_ms_ - audioFrame->elapsed_time_ms_;
       }
     }
   }
 
   return muted ? MixerParticipant::AudioFrameInfo::kMuted
                : MixerParticipant::AudioFrameInfo::kNormal;
 }
 
+MixerAudioSource::AudioFrameWithMuted Channel::GetAudioFrameWithMuted(
+    int32_t id,
+    int sample_rate_hz) {
+  mix_audio_frame_.sample_rate_hz_ = sample_rate_hz;
+  auto frame_info = GetAudioFrameWithMuted(id, &mix_audio_frame_);
+  MixerAudioSource::AudioFrameInfo new_audio_frame_info;

[the sun, 2016/10/03 11:41:26]

Init to kError and omit the default section of the switch

[aleloi, 2016/10/03 12:57:28]

Then the compiler warns about not handling every case.

[the sun, 2016/10/04 20:41:12]

Right, handle all cases in the switch but leave out the catch-all "default"
since you will be warned if you're missing something. And also always initialize
variables, such as this one. It happens that code is moved around, and a defined
state is much easier to track if a problem surfaces.

[aleloi, 2016/10/05 13:56:51]

Thanks, that seems a good tip for the future :)

+  switch (frame_info) {
+    case MixerParticipant::AudioFrameInfo::kNormal:
+      new_audio_frame_info = MixerAudioSource::AudioFrameInfo::kNormal;
+      break;
+    case MixerParticipant::AudioFrameInfo::kMuted:
+      new_audio_frame_info = MixerAudioSource::AudioFrameInfo::kMuted;
+      break;
+    default:
+      new_audio_frame_info = MixerAudioSource::AudioFrameInfo::kError;
+  }
+  return {&mix_audio_frame_, new_audio_frame_info};
+}
+
 int32_t Channel::NeededFrequency(int32_t id) const {
   WEBRTC_TRACE(kTraceStream, kTraceVoice, VoEId(_instanceId, _channelId),
                "Channel::NeededFrequency(id=%d)", id);
 
   int highestNeeded = 0;
 
   // Determine highest needed receive frequency
   int32_t receiveFrequency = audio_coding_->ReceiveFrequency();
 
   // Return the bigger of playout and receive frequency in the ACM.
@@ skipping 2497 matching lines @@
   int64_t min_rtt = 0;
   if (_rtpRtcpModule->RTT(remoteSSRC, &rtt, &avg_rtt, &min_rtt, &max_rtt) !=
       0) {
     return 0;
   }
   return rtt;
 }
 
 }  // namespace voe
 }  // namespace webrtc