relnote: Don't add burst tokens to QUIC's PacingSender when in recovery.

net/quic/congestion_control/pacing_sender.cc

 // Copyright (c) 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "net/quic/congestion_control/pacing_sender.h"
 
 using std::min;
 
 namespace net {
 
@@ skipping 44 matching lines @@
     QuicByteCount bytes_in_flight,
     QuicPacketNumber packet_number,
     QuicByteCount bytes,
     HasRetransmittableData has_retransmittable_data) {
   const bool in_flight =
       sender_->OnPacketSent(sent_time, bytes_in_flight, packet_number, bytes,
                             has_retransmittable_data);
   if (has_retransmittable_data != HAS_RETRANSMITTABLE_DATA) {
     return in_flight;
   }
-  if (bytes_in_flight == 0) {
+  // If in recovery, the connection is not coming out of quiescence.
+  if (bytes_in_flight == 0 && !sender_->InRecovery()) {
     // Add more burst tokens anytime the connection is leaving quiescence, but
     // limit it to the equivalent of a single bulk write, not exceeding the
     // current CWND in packets.
     burst_tokens_ = min(
         initial_packet_burst_,
         static_cast<uint32>(sender_->GetCongestionWindow() / kDefaultTCPMSS));
   }
   if (burst_tokens_ > 0) {
     --burst_tokens_;
     was_last_send_delayed_ = false;
@@ skipping 96 matching lines @@
 
 QuicByteCount PacingSender::GetSlowStartThreshold() const {
   return sender_->GetSlowStartThreshold();
 }
 
 CongestionControlType PacingSender::GetCongestionControlType() const {
   return sender_->GetCongestionControlType();
 }
 
 }  // namespace net