dart2js + html: getBoundingClientRect() returns a ClientRect

tools/dom/scripts/dartmetadata.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 to provide Dart metadata for
 DOM APIs.
 """
 
 import copy
@@ skipping 88 matching lines @@
     ],
     'DocumentFragment.querySelectorAll': [
       "@Creates('NodeList')",
       "@Returns('NodeList')",
     ],
     'Element.querySelectorAll': [
       "@Creates('NodeList')",
       "@Returns('NodeList')",
     ],
 
+    'Element.getBoundingClientRect': [
+        "@Creates('_ClientRect')",
+        "@Returns('_ClientRect|Null')", # TODO(sra): Verify and remove Null.
+    ],
+
     # Methods returning Window can return a local window, or a cross-frame
     # window (=Object) that needs wrapping.
     'Window': [
       "@Creates('Window|=Object')",
       "@Returns('Window|=Object')",
     ],
 
     'Window.openDatabase': [
       "@Creates('SqlDatabase')",
     ],
@@ skipping 802 matching lines @@
       pass
     else:
       _logger.warn('Unknown support_level - %s:%s' % (interface_id, member_id))
 
     return annotations
 
   def Flush(self):
     json_file = open(self._api_status_path, 'w+')
     json.dump(self._types, json_file, indent=2, separators=(',', ': '), sort_keys=True)
     json_file.close()