Reland of quest keyframes more frequently on stream start/decoding error.

webrtc/video/video_receive_stream.h

Index: webrtc/video/video_receive_stream.h
diff --git a/webrtc/video/video_receive_stream.h b/webrtc/video/video_receive_stream.h
index 3ae092fe6e3a4ed42e81cd5b14a7285bc04da84f..6a5386593df182a585c764e9a61cbf4ab68df4ba 100644
--- a/webrtc/video/video_receive_stream.h
+++ b/webrtc/video/video_receive_stream.h
@@ -148,6 +148,13 @@ class VideoReceiveStream : public webrtc::VideoReceiveStream,
 
   std::unique_ptr<RtpStreamReceiverInterface> media_receiver_;
   std::unique_ptr<RtpStreamReceiverInterface> rtx_receiver_;
+
+  // Whenever we are in an undecodable state (stream has just started or due to
+  // a decoding error) we require a keyframe to restart the stream.
+  bool keyframe_required_ = true;
+
+  // If we have successfully decoded any frame.
+  bool frame_decoded_ = false;
 };
 }  // namespace internal
 }  // namespace webrtc