relnote: Refactor QuicAckFrame::missing_packets to support a change to a

net/quic/quic_sent_packet_manager.cc

 // Copyright 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/quic_sent_packet_manager.h"
 
 #include <algorithm>
 
 #include "base/logging.h"
 #include "base/stl_util.h"
@@ skipping 253 matching lines @@
 
   if (debug_delegate_ != nullptr) {
     debug_delegate_->OnIncomingAck(ack_frame, ack_receive_time,
                                    unacked_packets_.largest_observed(),
                                    rtt_updated, GetLeastUnacked());
   }
 }
 
 void QuicSentPacketManager::UpdatePacketInformationReceivedByPeer(
     const QuicAckFrame& ack_frame) {
-  if (ack_frame.missing_packets.empty()) {
+  if (ack_frame.missing_packets.Empty()) {
     least_packet_awaited_by_peer_ = ack_frame.largest_observed + 1;
   } else {
-    least_packet_awaited_by_peer_ = *(ack_frame.missing_packets.begin());
+    least_packet_awaited_by_peer_ = ack_frame.missing_packets.Min();
   }
 }
 
 void QuicSentPacketManager::MaybeInvokeCongestionEvent(
     bool rtt_updated, QuicByteCount bytes_in_flight) {
   if (!rtt_updated && packets_acked_.empty() && packets_lost_.empty()) {
     return;
   }
   send_algorithm_->OnCongestionEvent(rtt_updated, bytes_in_flight,
                                      packets_acked_, packets_lost_);
@@ skipping 11 matching lines @@
   QuicTime::Delta delta_largest_observed =
       ack_frame.delta_time_largest_observed;
   QuicPacketNumber packet_number = unacked_packets_.GetLeastUnacked();
   for (QuicUnackedPacketMap::const_iterator it = unacked_packets_.begin();
        it != unacked_packets_.end(); ++it, ++packet_number) {
     if (packet_number > ack_frame.largest_observed) {
       // These packets are still in flight.
       break;
     }
 
-    if (ContainsKey(ack_frame.missing_packets, packet_number)) {
+    if (ack_frame.missing_packets.Contains(packet_number)) {
       // Don't continue to increase the nack count for packets not in flight.
       if (!it->in_flight) {
         continue;
       }
       // Consider it multiple nacks when there is a gap between the missing
       // packet and the largest observed, since the purpose of a nack
       // threshold is to tolerate re-ordering.  This handles both StretchAcks
       // and Forward Acks.
       // The nack count only increases when the largest observed increases.
       QuicPacketCount min_nacks = ack_frame.largest_observed - packet_number;
@@ skipping 624 matching lines @@
   // Set up a pacing sender with a 1 millisecond alarm granularity, the same as
   // the default granularity of the Linux kernel's FQ qdisc.
   using_pacing_ = true;
   send_algorithm_.reset(
       new PacingSender(send_algorithm_.release(),
                        QuicTime::Delta::FromMilliseconds(1),
                        kInitialUnpacedBurst));
 }
 
 }  // namespace net