Minimal fix to get cross frame tests working.

lib/dom/scripts/systemhtml.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.
 
 """This module provides shared functionality for the system to generate
 Dart:html APIs from the IDL database."""
 
 from systemfrog import *
 from systeminterface import *
@@ skipping 250 matching lines @@
     "Node.removeEventListener",
     "Node.get:nodeValue",
     "Node.set:nodeValue",
     "Node.get:CDATA_SECTION_NODE",
     "Node.get:nodeName",
     "Node.addEventListener",
     "Node.lookupPrefix",
     "Node.get:PROCESSING_INSTRUCTION_NODE",
     "Notification.dispatchEvent",
     "Notification.addEventListener",
-    "Notification.removeEventListener"])
+    "Notification.removeEventListener",
+    "IFrameElement.get:contentDocument",
+    "IFrameElement.get:contentWindow",
+    "Window.get:frameElement",
+    "Window.get:top",
+    ])
 
 # Events without onEventName attributes in the  IDL we want to support.
 # We can automatically extract most event event names by checking for
 # onEventName methods in the IDL but some events aren't listed so we need
 # to manually add them here so that they are easy for users to find.
 _html_manual_events = {
   'Element': ['touchleave', 'touchenter', 'webkitTransitionEnd'],
   'Window': ['DOMContentLoaded']
 }
 
@@ skipping 1415 matching lines @@
     # dispatch has removed f(X), leaving only f(Y), but there is no guarantee
     # that Y = Z-X, so we need to check for Y.
     true_code = emitter.Emit(
         '$(INDENT)if ($COND) {\n'
         '$!TRUE'
         '$(INDENT)}\n',
         COND=test, INDENT=indent)
     self.GenerateDispatch(
         true_code, info, indent + '  ', position + 1, positive)
     return True