Let VideoRenderFrames::FrameToRender return rtc::Optional

webrtc/common_video/incoming_video_stream.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 157 matching lines @@
 
 bool IncomingVideoStream::IncomingVideoStreamProcess() {
   if (kEventError != deliver_buffer_event_->Wait(kEventMaxWaitTimeMs)) {
     rtc::CritScope cs(&thread_critsect_);
     if (incoming_render_thread_ == NULL) {
       // Terminating
       return false;
     }
 
     // Get a new frame to render and the time for the frame after this one.
-    VideoFrame frame_to_render;
+    rtc::Optional<VideoFrame> frame_to_render;
     uint32_t wait_time;
     {
       rtc::CritScope cs(&buffer_critsect_);
       frame_to_render = render_buffers_->FrameToRender();
       wait_time = render_buffers_->TimeToNextFrameRelease();
     }
 
     // Set timer for next frame to render.
     if (wait_time > kEventMaxWaitTimeMs) {
       wait_time = kEventMaxWaitTimeMs;
     }
     deliver_buffer_event_->StartTimer(false, wait_time);
 
-    DeliverFrame(frame_to_render);
+    if (frame_to_render)
+      DeliverFrame(*frame_to_render);
   }
   return true;
 }
 
 void IncomingVideoStream::DeliverFrame(const VideoFrame& video_frame) {
   rtc::CritScope cs(&thread_critsect_);
-  if (video_frame.IsZeroSize()) {
-    // No frame.
-    return;
-  }
 
   // Send frame for rendering.
   if (external_callback_) {
     external_callback_->OnFrame(video_frame);
   } else if (render_callback_) {
     render_callback_->OnFrame(video_frame);
   }
 }
 
 }  // namespace webrtc