Refresh dart:dom libraries from WebKit

client/dom/generated/src/interface/EventSource.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 EventSource extends EventTarget {
 
   static final int CLOSED = 2;
 
   static final int CONNECTING = 0;
 
   static final int OPEN = 1;
 
   String get URL();
 
   int get readyState();
 
+  String get url();
+
   void addEventListener(String type, EventListener listener, [bool useCapture]);
 
   void close();
 
   bool dispatchEvent(Event evt);
 
   void removeEventListener(String type, EventListener listener, [bool useCapture]);
 }