Don't copy the QuicAckFrame into the QuicPacketGenerator. Protected by quic_dont_copy_acks.

net/quic/test_tools/quic_connection_peer.h

 // Copyright (c) 2012 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_TEST_TOOLS_QUIC_CONNECTION_PEER_H_
 #define NET_QUIC_TEST_TOOLS_QUIC_CONNECTION_PEER_H_
 
 #include "base/macros.h"
 #include "net/base/ip_endpoint.h"
 #include "net/quic/quic_connection.h"
@@ skipping 22 matching lines @@
 // Peer to make public a number of otherwise private QuicConnection methods.
 class QuicConnectionPeer {
  public:
   static void SendAck(QuicConnection* connection);
 
   static void SetSendAlgorithm(QuicConnection* connection,
                                SendAlgorithmInterface* send_algorithm);
 
   static void PopulateAckFrame(QuicConnection* connection, QuicAckFrame* ack);
 
+  static const QuicFrame GetUpdatedAckFrame(QuicConnection* connection);
+
   static void PopulateStopWaitingFrame(QuicConnection* connection,
                                        QuicStopWaitingFrame* stop_waiting);
 
   static QuicConnectionVisitorInterface* GetVisitor(QuicConnection* connection);
 
   static QuicPacketCreator* GetPacketCreator(QuicConnection* connection);
 
   static QuicPacketGenerator* GetPacketGenerator(QuicConnection* connection);
 
   static QuicSentPacketManager* GetSentPacketManager(
@@ skipping 69 matching lines @@
 
  private:
   DISALLOW_COPY_AND_ASSIGN(QuicConnectionPeer);
 };
 
 }  // namespace test
 
 }  // namespace net
 
 #endif  // NET_QUIC_TEST_TOOLS_QUIC_CONNECTION_PEER_H_