Don't report packets with id -1 to the transport feedback adapter as they provide no value.

webrtc/modules/congestion_controller/congestion_controller.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 272 matching lines @@
   }
   {
     rtc::CritScope cs(&critsect_);
     network_state_ = state;
   }
   probe_controller_->OnNetworkStateChanged(state);
   MaybeTriggerOnNetworkChanged();
 }
 
 void CongestionController::OnSentPacket(const rtc::SentPacket& sent_packet) {
+  // We're not interested in packets without an id, which may be stun packets,
+  // etc, sent on the same transport.
+  if (sent_packet.packet_id == -1)
+    return;
   transport_feedback_adapter_.OnSentPacket(sent_packet.packet_id,
                                            sent_packet.send_time_ms);
 }
 
 void CongestionController::OnRttUpdate(int64_t avg_rtt_ms, int64_t max_rtt_ms) {
   remote_bitrate_estimator_->OnRttUpdate(avg_rtt_ms, max_rtt_ms);
   transport_feedback_adapter_.OnRttUpdate(avg_rtt_ms, max_rtt_ms);
 }
 
 int64_t CongestionController::TimeUntilNextProcess() {
@@ skipping 57 matching lines @@
 bool CongestionController::IsSendQueueFull() const {
   return pacer_->ExpectedQueueTimeMs() > PacedSender::kMaxQueueLengthMs;
 }
 
 bool CongestionController::IsNetworkDown() const {
   rtc::CritScope cs(&critsect_);
   return network_state_ == kNetworkDown;
 }
 
 }  // namespace webrtc