| Index: Source/core/editing/Selection.idl | 
| diff --git a/Source/core/editing/Selection.idl b/Source/core/editing/Selection.idl | 
| index a7ad07b414cbc02147f84e07a9b0386b600e5cb4..e1b3fbbe184f3717b4790b836fbd859c80cfdc3b 100644 | 
| --- a/Source/core/editing/Selection.idl | 
| +++ b/Source/core/editing/Selection.idl | 
| @@ -60,8 +60,7 @@ | 
| [Default=Undefined] optional long extentOffset); | 
| [RaisesException, TypeChecking=Interface] void selectAllChildren(Node node); | 
| [CustomElementCallbacks] void deleteFromDocument(); | 
| -    // TODO(philipj): The arguments should not be optional. | 
| -    [MeasureAs=SelectionContainsNode] boolean containsNode([Default=Undefined] optional Node node, [Default=Undefined] optional boolean allowPartialContainment); | 
| +    [MeasureAs=SelectionContainsNode, TypeChecking=Interface] boolean containsNode(Node node, optional boolean allowPartialContainment = false); | 
| // TODO(philipj): The spec does not use [NotEnumerable]. See also: | 
| // https://codereview.chromium.org/345983004/ | 
| // https://www.w3.org/Bugs/Public/show_bug.cgi?id=26179 | 
|  |