Add reprioritization to socket pools.

net/socket/client_socket_handle.h

Index: net/socket/client_socket_handle.h
diff --git a/net/socket/client_socket_handle.h b/net/socket/client_socket_handle.h
index de0381f674b90e0f61a3054ac0083f2f583f5fec..ac2526679f69f5a06864f3c51ed353532b10aebb 100644
--- a/net/socket/client_socket_handle.h
+++ b/net/socket/client_socket_handle.h
@@ -91,6 +91,12 @@ class NET_EXPORT ClientSocketHandle {
            PoolType* pool,
            const NetLogWithSource& net_log);
 
+  // Changes the priority of the ClientSocketHandle to the passed value.
+  // This function is a no-op if |priority| is the same as the current
+  // priority, of if Init() has not been called since the last time
+  // the ClientSocketHandle was reset.
+  void SetPriority(RequestPriority priority);
+
   // An initialized handle can be reset, which causes it to return to the
   // un-initialized state.  This releases the underlying socket, which in the
   // case of a socket that still has an established connection, indicates that