Missed a change in the rename from initCustomEvent -> $dom_initCustomEvent.

lib/html/scripts/htmlrenamer.py

 #!/usr/bin/python
 # Copyright (c) 2012, 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.
 
 html_interface_renames = {
     'DOMFormData': 'FormData',
     'DOMWindow': 'Window',
     'WebKitAnimation': 'Animation',
     'WebKitAnimationEvent': 'AnimationEvent',
@@ skipping 10 matching lines @@
     'XMLHttpRequest': 'HttpRequest',
     'XMLHttpRequestException': 'HttpRequestException',
     'XMLHttpRequestProgressEvent': 'HttpRequestProgressEvent',
     'XMLHttpRequestUpload': 'HttpRequestUpload',
 }
 
 # Members from the standard dom that should not be exposed publicly in dart:html
 # but need to be exposed internally to implement dart:html on top of a standard
 # browser.
 _private_html_members = set([
+  'CustomEvent.initCustomEvent',
   'Document.createElement',
   'Document.createElementNS',
   'Document.createEvent',
   'Document.createTextNode',
   'Document.createTouchList',
   'Document.getElementById',
   'Document.getElementsByClassName',
   'Document.getElementsByName',
   'Document.getElementsByTagName',
   'Document.querySelector',
@@ skipping 272 matching lines @@
 
   def _FindMatch(self, interface, member, member_prefix, candidates):
     for interface in self._database.Hierarchy(interface):
       html_interface_name = self.RenameInterface(interface)
       member_name = html_interface_name + '.' + member
       if member_name in candidates:
         return member_name
       member_name = html_interface_name + '.' + member_prefix + member
       if member_name in candidates:
         return member_name