Add reprioritization to socket pools.

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 <memory>
 #include <string>
@@ skipping 106 matching lines @@
   // group.  It uses |params| to control how to connect the sockets.   The
   // ClientSocketPool will assign a priority to the new connections, if any.
   // This priority will probably be lower than all others, since this method
   // is intended to make sure ahead of time that |num_sockets| sockets are
   // available to talk to a host.
   virtual void RequestSockets(const std::string& group_name,
                               const void* params,
                               int num_sockets,
                               const NetLogWithSource& net_log) = 0;
 
+  // Called to change the priority of a RequestSocket call that returned
+  // ERR_IO_PENDING and has not yet asynchronously completed.  The same handle
+  // parameter must be passed to this method as was passed to the
+  // RequestSocket call being modified.
+  // This function is a no-op if |priority| is the same as the current
+  // request priority.
+  virtual void SetPriority(const std::string& group_name,
+                           ClientSocketHandle* handle,
+                           RequestPriority priority) = 0;
+
   // Called to cancel a RequestSocket call that returned ERR_IO_PENDING.  The
   // same handle parameter must be passed to this method as was passed to the
   // RequestSocket call being cancelled.  The associated CompletionCallback is
   // not run.  However, for performance, we will let one ConnectJob complete
   // and go idle.
   virtual void CancelRequest(const std::string& group_name,
                              ClientSocketHandle* handle) = 0;
 
   // Called to release a socket once the socket is no longer needed.  If the
   // socket still has an established connection, then it will be added to the
@@ skipping 61 matching lines @@
     const std::string& group_name,
     const scoped_refptr<typename PoolType::SocketParams>& params,
     int num_sockets,
     const NetLogWithSource& net_log) {
   pool->RequestSockets(group_name, &params, num_sockets, net_log);
 }
 
 }  // namespace net
 
 #endif  // NET_SOCKET_CLIENT_SOCKET_POOL_H_