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

net/socket/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_SOCKET_CLIENT_SOCKET_POOL_H_
 #define NET_SOCKET_CLIENT_SOCKET_POOL_H_
 
 #include <deque>
 #include <string>
 
@@ skipping 97 matching lines @@
   // set of idle sockets to be used to satisfy future RequestSocket calls.
   // Otherwise, the StreamSocket is destroyed.  |id| is used to differentiate
   // between updated versions of the same pool instance.  The pool's id will
   // change when it flushes, so it can use this |id| to discard sockets with
   // mismatched ids.
   virtual void ReleaseSocket(const std::string& group_name,
                              StreamSocket* socket,
                              int id) = 0;
 
   // This flushes all state from the ClientSocketPool.  This means that all
-  // idle and connecting sockets are discarded.  Active sockets being
-  // held by ClientSocketPool clients will be discarded when released back to
-  // the pool.  Does not flush any pools wrapped by |this|.
-  virtual void Flush() = 0;
+  // idle and connecting sockets are discarded with the given |error|.
+  // Active sockets being held by ClientSocketPool clients will be discarded
+  // when released back to the pool.
+  // Does not flush any pools wrapped by |this|.
+  virtual void FlushWithError(int error) = 0;
 
   // Returns true if a there is currently a request blocked on the
   // per-pool (not per-host) max socket limit.
   virtual bool IsStalled() const = 0;
 
   // Called to close any idle connections held by the connection manager.
   virtual void CloseIdleSockets() = 0;
 
   // The total number of idle sockets in the pool.
   virtual int IdleSocketCount() const = 0;
@@ skipping 78 matching lines @@
                            const scoped_refptr<SocketParams>& params,
                            int num_sockets,
                            const BoundNetLog& net_log) {
   CheckIsValidSocketParamsForPool<PoolType, SocketParams>();
   pool->RequestSockets(group_name, &params, num_sockets, net_log);
 }
 
 }  // namespace net
 
 #endif  // NET_SOCKET_CLIENT_SOCKET_POOL_H_