Remove the fallback from SOCKSv4 to SOCKSv4a.

net/socket/socks_client_socket.h

 // Copyright (c) 2011 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_
 #pragma once
 
 #include <string>
 
@@ skipping 64 matching lines @@
   enum State {
     STATE_RESOLVE_HOST,
     STATE_RESOLVE_HOST_COMPLETE,
     STATE_HANDSHAKE_WRITE,
     STATE_HANDSHAKE_WRITE_COMPLETE,
     STATE_HANDSHAKE_READ,
     STATE_HANDSHAKE_READ_COMPLETE,
     STATE_NONE,
   };
 
-  // The SOCKS proxy connection either has the hostname resolved via the
-  // client or via the server. This enum stores the state of the SOCKS
-  // connection. If the client can resolve the hostname, the connection is
-  // SOCKS4, otherwise it is SOCKS4A.
-  enum SocksVersion {
-    kSOCKS4Unresolved,
-    kSOCKS4,
-    kSOCKS4a,
-  };
-
   void DoCallback(int result);
   void OnIOComplete(int result);
 
   int DoLoop(int last_io_result);
   int DoResolveHost();
   int DoResolveHostComplete(int result);
   int DoHandshakeRead();
   int DoHandshakeReadComplete(int result);
   int DoHandshakeWrite();
   int DoHandshakeWriteComplete(int result);
 
   const std::string BuildHandshakeWriteBuffer() const;
 
   CompletionCallbackImpl<SOCKSClientSocket> io_callback_;
 
   // Stores the underlying socket.
   scoped_ptr<ClientSocketHandle> transport_;
 
   State next_state_;
-  SocksVersion socks_version_;
 
   // Stores the callback to the layer above, called on completing Connect().
   CompletionCallback* user_callback_;
 
   // This IOBuffer is used by the class to read and write
   // SOCKS handshake data. The length contains the expected size to
   // read or write.
   scoped_refptr<IOBuffer> handshake_buf_;
 
   // While writing, this buffer stores the complete write handshake data.
@@ skipping 14 matching lines @@
   HostResolver::RequestInfo host_request_info_;
 
   BoundNetLog net_log_;
 
   DISALLOW_COPY_AND_ASSIGN(SOCKSClientSocket);
 };
 
 }  // namespace net
 
 #endif  // NET_SOCKET_SOCKS_CLIENT_SOCKET_H_