Add DefaultListenSocket.

net/base/listen_socket.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/base/listen_socket.h"
-
-namespace net {
-
-ListenSocket::ListenSocket(ListenSocketDelegate* del) : socket_delegate_(del) {}
-
-ListenSocket::~ListenSocket() {}
-
-void ListenSocket::Send(const char* bytes, int len, bool append_linefeed) {
-  SendInternal(bytes, len);
-  if (append_linefeed)
-    SendInternal("\r\n", 2);
-}
-
-void ListenSocket::Send(const std::string& str, bool append_linefeed) {
-  Send(str.data(), static_cast<int>(str.length()), append_linefeed);
-}
-
-}  // namespace net