Avoid busy looping as the VideoReceiveStream is shut down.

webrtc/video/video_receive_stream.cc

 /*
  *  Copyright (c) 2013 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 450 matching lines @@
   RTC_NOTREACHED();
   return 0;
 }
 
 void VideoReceiveStream::SetMinimumPlayoutDelay(int delay_ms) {
   RTC_DCHECK_RUN_ON(&module_process_thread_checker_);
   video_receiver_.SetMinimumPlayoutDelay(delay_ms);
 }
 
 bool VideoReceiveStream::DecodeThreadFunction(void* ptr) {
-  static_cast<VideoReceiveStream*>(ptr)->Decode();
-  return true;
+  return static_cast<VideoReceiveStream*>(ptr)->Decode();
 }
 
-void VideoReceiveStream::Decode() {
+bool VideoReceiveStream::Decode() {
   static const int kMaxWaitForFrameMs = 3000;
   std::unique_ptr<video_coding::FrameObject> frame;
   video_coding::FrameBuffer::ReturnReason res =
       frame_buffer_->NextFrame(kMaxWaitForFrameMs, &frame);
 
   if (res == video_coding::FrameBuffer::ReturnReason::kStopped)
-    return;
+    return false;
 
   if (frame) {
     if (video_receiver_.Decode(frame.get()) == VCM_OK)
       rtp_stream_receiver_.FrameDecoded(frame->picture_id);
   } else {
     LOG(LS_WARNING) << "No decodable frame in " << kMaxWaitForFrameMs
                     << " ms, requesting keyframe.";
     RequestKeyFrame();
   }
+  return true;
 }
 }  // namespace internal
 }  // namespace webrtc