First step to remove SingleRequestHostResolver.

net/socket/socks_client_socket.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_SOCKET_SOCKS_CLIENT_SOCKET_H_
 #define NET_SOCKET_SOCKS_CLIENT_SOCKET_H_
 
 #include <stddef.h>
 #include <stdint.h>
 
 #include <memory>
 #include <string>
 
 #include "base/gtest_prod_util.h"
 #include "base/macros.h"
 #include "base/memory/ref_counted.h"
 #include "net/base/address_list.h"
 #include "net/base/completion_callback.h"
 #include "net/base/net_errors.h"
 #include "net/dns/host_resolver.h"
-#include "net/dns/single_request_host_resolver.h"
 #include "net/log/net_log.h"
 #include "net/socket/stream_socket.h"
 
 namespace net {
 
 class ClientSocketHandle;
 class BoundNetLog;
 
 // The SOCKS client socket implementation
 class NET_EXPORT_PRIVATE SOCKSClientSocket : public StreamSocket {
@@ skipping 92 matching lines @@
   bool completed_handshake_;
 
   // These contain the bytes sent / received by the SOCKS handshake.
   size_t bytes_sent_;
   size_t bytes_received_;
 
   // This becomes true when the socket is used to send or receive data.
   bool was_ever_used_;
 
   // Used to resolve the hostname to which the SOCKS proxy will connect.
-  SingleRequestHostResolver host_resolver_;
+  HostResolver* host_resolver_;
+  std::unique_ptr<HostResolver::Request> request_;
   AddressList addresses_;
   HostResolver::RequestInfo host_request_info_;
   RequestPriority priority_;
 
   BoundNetLog net_log_;
 
   DISALLOW_COPY_AND_ASSIGN(SOCKSClientSocket);
 };
 
 }  // namespace net
 
 #endif  // NET_SOCKET_SOCKS_CLIENT_SOCKET_H_