Update to new Webkit additions for custom elements

tools/dom/scripts/generate_blink_file.py

 #!/usr/bin/python
 #
 # Copyright (c) 2014, 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.
 
 """Generates sdk/lib/_blink/dartium/_blink_dartium.dart file."""
 
 import os
 from sets import Set
@@ skipping 115 matching lines @@
   static void spawnDomHelper(Function f, int replyTo) native "Utils_spawnDomHelper";
 
   static register(document, tag, customType, extendsTagName) native "Utils_register";
 
   // Defines an interceptor if there is an appropriate JavaScript prototype to define it on.
   // In any case, returns a typed JS wrapper compatibile with dart:html and the new
   // typed JS Interop.
   static defineInterceptorCustomElement(jsObject, Type type) native "Utils_defineInterceptorCustomElement";
   static defineInterceptor(jsObject, Type type) native "Utils_defineInterceptor";
   static setInstanceInterceptor(o, Type type, {bool customElement: false}) native "Utils_setInstanceInterceptor";
+  static setInstanceInterceptorCustomUpgrade(o) native "Utils_setInstanceInterceptorCustomUpgrade";
 
   // This method will throw if the element isn't actually a real Element.
   static initializeCustomElement(element) native "Utils_initializeCustomElement";
 }
 
 class Blink_DOMStringMap {
   // _DOMStringMap native entry  points
   static containsKey(_DOMStringMap, key) native "DOMStringMap_containsKey_Callback";
 
   static item(_DOMStringMap, key) native "DOMStringMap_item_Callback";
@@ skipping 378 matching lines @@
     else:
       arguments = []
       for i in range(0, callback_index):
         arguments.append(ARGUMENT_NUM % i)
       argument_list = ', '.join(arguments)
       if operation.is_static:
         class_property = CLASS_STATIC % interface.id
         blink_file.write(Select_Stub(STATIC_OPERATION_ARGS, is_native) % (name, callback_index, argument_list, class_property, interface.id, name, argument_list))
       else:
         blink_file.write(Select_Stub(OPERATION_ARGS, is_native) % (name, callback_index, argument_list, interface.id, name, argument_list))