Fix net_export.h includes.

net/socket/socks5_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_SOCKS5_CLIENT_SOCKET_H_
 #define NET_SOCKET_SOCKS5_CLIENT_SOCKET_H_
 
 #include <stddef.h>
 #include <stdint.h>
 
 #include <memory>
 #include <string>
 
 #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/base/net_export.h"
 #include "net/dns/host_resolver.h"
 #include "net/log/net_log_with_source.h"
 #include "net/socket/stream_socket.h"
 #include "url/gurl.h"
 
 namespace net {
 
 class ClientSocketHandle;
 
 // This StreamSocket is used to setup a SOCKSv5 handshake with a socks proxy.
@@ skipping 124 matching lines @@
   HostResolver::RequestInfo host_request_info_;
 
   NetLogWithSource net_log_;
 
   DISALLOW_COPY_AND_ASSIGN(SOCKS5ClientSocket);
 };
 
 }  // namespace net
 
 #endif  // NET_SOCKET_SOCKS5_CLIENT_SOCKET_H_