Only create H264 frames if there are no gaps in the packet sequence number.

webrtc/video/rtp_video_stream_receiver.cc

Index: webrtc/video/rtp_video_stream_receiver.cc
diff --git a/webrtc/video/rtp_video_stream_receiver.cc b/webrtc/video/rtp_video_stream_receiver.cc
index 14e5958c0bb48c228582109e06fcbdeeea54c884..f1e530d3a7586dfac75fb06c192755ec4d75389c 100644
--- a/webrtc/video/rtp_video_stream_receiver.cc
+++ b/webrtc/video/rtp_video_stream_receiver.cc
@@ -245,6 +245,7 @@ int32_t RtpVideoStreamReceiver::OnReceivedPayloadData(
   // correctly calculate frame references.
   if (packet.sizeBytes == 0) {
     reference_finder_->PaddingReceived(packet.seqNum);
+    packet_buffer_->PaddingReceived(packet.seqNum);
     return 0;
   }