Refresh dart:dom libraries from WebKit

client/dom/generated/src/interface/WebSocket.dart

 // Copyright (c) 2011, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 // WARNING: Do not edit - generated code.
 
 interface WebSocket extends EventTarget default _WebSocketFactoryProvider {
 
   WebSocket(String url);
 
@@ skipping 12 matching lines @@
   void set binaryType(String value);
 
   int get bufferedAmount();
 
   String get extensions();
 
   String get protocol();
 
   int get readyState();
 
+  String get url();
+
   void addEventListener(String type, EventListener listener, [bool useCapture]);
 
   void close([int code, String reason]);
 
   bool dispatchEvent(Event evt);
 
   void removeEventListener(String type, EventListener listener, [bool useCapture]);
 
   bool send(String data);
 }