Change the wire format of the ack frame to include a compressed version

net/quic/congestion_control/receive_algorithm_interface.cc

 // 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.
 
 #include "net/quic/congestion_control/receive_algorithm_interface.h"
 
 #include "net/quic/congestion_control/tcp_receiver.h"
 
 namespace net {
 
 // Factory for receive side congestion control algorithm.
 ReceiveAlgorithmInterface* ReceiveAlgorithmInterface::Create(
     CongestionFeedbackType type) {
   switch (type) {
     case kTCP:
       return new TcpReceiver();
-    case kTimestamp:
-      LOG(DFATAL) << "Timestamp congestion feedback is not supported";
-      return NULL;
   }
   return NULL;
 }
 
 }  // namespace net