Remove an unneeded hash_set from QuicAckNotifierManager.

net/quic/quic_ack_notifier.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_ack_notifier.h"
 
 #include <set>
 
 #include "base/logging.h"
 #include "base/stl_util.h"
@@ skipping 18 matching lines @@
 QuicAckNotifier::~QuicAckNotifier() {
 }
 
 void QuicAckNotifier::OnSerializedPacket() {
   ++unacked_packets_;
 }
 
 bool QuicAckNotifier::OnAck(QuicPacketSequenceNumber sequence_number,
                             QuicTime::Delta delta_largest_observed) {
   if (unacked_packets_ <= 0) {
-    LOG(DFATAL) << "Acked more packets than were tracked.";
+    LOG(DFATAL) << "Acked more packets than were tracked."
+                << " unacked_packets:" << unacked_packets_;
     return true;
   }
   --unacked_packets_;
-  if (IsEmpty()) {
+  if (!HasUnackedPackets()) {
     // We have seen all the sequence numbers we were waiting for, trigger
     // callback notification.
     delegate_->OnAckNotification(retransmitted_packet_count_,
                                  retransmitted_byte_count_,
                                  delta_largest_observed);
     return true;
   }
   return false;
 }
 
+bool QuicAckNotifier::OnPacketAbandoned() {
+  if (unacked_packets_ <= 0) {
+    LOG(DFATAL) << "Abandoned more packets than were tracked."
+                << " unacked_packets:" << unacked_packets_;
+    return true;
+  }
+  --unacked_packets_;
+  return unacked_packets_ == 0;
+}
+
 void QuicAckNotifier::OnPacketRetransmitted(int packet_payload_size) {
   ++retransmitted_packet_count_;
   retransmitted_byte_count_ += packet_payload_size;
 }
 
 };  // namespace net