Replace the map in QuicAckNotifier with a counter.

net/quic/quic_ack_notifier_manager.h

 // 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.
 
 #ifndef NET_QUIC_QUIC_ACK_NOTIFIER_MANAGER_H_
 #define NET_QUIC_QUIC_ACK_NOTIFIER_MANAGER_H_
 
 #include <list>
 #include <map>
 
@@ skipping 17 matching lines @@
 
   // Called when the connection receives a new AckFrame.  If |sequence_number|
   // exists in ack_notifier_map_ then the corresponding AckNotifiers will have
   // their OnAck method called.
   void OnPacketAcked(QuicPacketSequenceNumber sequence_number,
                      QuicTime::Delta delta_largest_observed);
 
   // If a packet has been retransmitted with a new sequence number, then this
   // will be called. It updates the mapping in ack_notifier_map_, and also
   // updates the internal set of sequence numbers in each matching AckNotifier.
-  void UpdateSequenceNumber(QuicPacketSequenceNumber old_sequence_number,
-                            QuicPacketSequenceNumber new_sequence_number);
+  void OnPacketRetransmitted(QuicPacketSequenceNumber old_sequence_number,
+                             QuicPacketSequenceNumber new_sequence_number,
+                             int packet_payload_size);
 
   // This is called after a packet has been serialized, is ready to be sent, and
   // contains retransmittable frames (which may have associated AckNotifiers).
   // If any of the retransmittable frames included in |serialized_packet| have
   // AckNotifiers registered, then add them to our internal map and additionally
   // inform the AckNotifier of the sequence number which it should track.
   void OnSerializedPacket(const SerializedPacket& serialized_packet);
 
  private:
   typedef std::list<QuicAckNotifier*> AckNotifierList;
@@ skipping 14 matching lines @@
   // number, call OnAck for all mapped AckNotifiers.
   // Does not own the AckNotifiers.
   AckNotifierMap ack_notifier_map_;
 
   DISALLOW_COPY_AND_ASSIGN(AckNotifierManager);
 };
 
 }  // namespace net
 
 #endif  // NET_QUIC_QUIC_ACK_NOTIFIER_MANAGER_H_