Make a QuicDefaultPacketWriter method virtual, and check member variable directly. No behavior chan…

net/tools/quic/quic_default_packet_writer.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/tools/quic/quic_default_packet_writer.h"
 
 #include "net/tools/quic/quic_socket_utils.h"
 
 namespace net {
 
 QuicDefaultPacketWriter::QuicDefaultPacketWriter(int fd)
     : fd_(fd), write_blocked_(false) {}
 
 QuicDefaultPacketWriter::~QuicDefaultPacketWriter() {}
 
 WriteResult QuicDefaultPacketWriter::WritePacket(const char* buffer,
                                                  size_t buf_len,
                                                  const IPAddress& self_address,
                                                  const IPEndPoint& peer_address,
                                                  PerPacketOptions* options) {
-  DCHECK(!IsWriteBlocked());
+  DCHECK(!write_blocked_);
   DCHECK(nullptr == options)
       << "QuicDefaultPacketWriter does not accept any options.";
   WriteResult result = QuicSocketUtils::WritePacket(fd_, buffer, buf_len,
                                                     self_address, peer_address);
   if (result.status == WRITE_STATUS_BLOCKED) {
     write_blocked_ = true;
   }
   return result;
 }
 
 bool QuicDefaultPacketWriter::IsWriteBlockedDataBuffered() const {
   return false;
 }
 
 bool QuicDefaultPacketWriter::IsWriteBlocked() const {
   return write_blocked_;
 }
 
 void QuicDefaultPacketWriter::SetWritable() {
   write_blocked_ = false;
 }
 
 QuicByteCount QuicDefaultPacketWriter::GetMaxPacketSize(
     const IPEndPoint& peer_address) const {
   return kMaxPacketSize;
 }
 
+void QuicDefaultPacketWriter::set_write_blocked(bool is_blocked) {
+  write_blocked_ = is_blocked;
+}
+
 }  // namespace net