Introduce ERR_NETWORK_CHANGED and allow URLFetcher to automatically retry on that error.

net/http/http_proxy_client_socket_pool.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_HTTP_HTTP_PROXY_CLIENT_SOCKET_POOL_H_
 #define NET_HTTP_HTTP_PROXY_CLIENT_SOCKET_POOL_H_
 
 #include <string>
 
 #include "base/basictypes.h"
@@ skipping 186 matching lines @@
                               int num_sockets,
                               const BoundNetLog& net_log) OVERRIDE;
 
   virtual void CancelRequest(const std::string& group_name,
                              ClientSocketHandle* handle) OVERRIDE;
 
   virtual void ReleaseSocket(const std::string& group_name,
                              StreamSocket* socket,
                              int id) OVERRIDE;
 
-  virtual void Flush() OVERRIDE;
+  virtual void FlushWithError(int error) OVERRIDE;
 
   virtual bool IsStalled() const OVERRIDE;
 
   virtual void CloseIdleSockets() OVERRIDE;
 
   virtual int IdleSocketCount() const OVERRIDE;
 
   virtual int IdleSocketCountInGroup(
       const std::string& group_name) const OVERRIDE;
 
@@ skipping 52 matching lines @@
 
   DISALLOW_COPY_AND_ASSIGN(HttpProxyClientSocketPool);
 };
 
 REGISTER_SOCKET_PARAMS_FOR_POOL(HttpProxyClientSocketPool,
                                 HttpProxySocketParams);
 
 }  // namespace net
 
 #endif  // NET_HTTP_HTTP_PROXY_CLIENT_SOCKET_POOL_H_