IDL: make optional arguments (without default) explicit sometimes

Source/core/editing/Selection.idl

 /*
  * Copyright (C) 2007 Apple Inc.  All rights reserved.
  * Copyright (C) 2009 Google Inc.  All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  *
  * 1.  Redistributions of source code must retain the above copyright
  *     notice, this list of conditions and the following disclaimer.
@@ skipping 36 matching lines @@
     readonly attribute boolean isCollapsed;
     [RaisesException, TypeChecking=Interface] void collapse(Node node, optional long offset);
     [RaisesException] void collapseToStart();
     [RaisesException] void collapseToEnd();
 
     // FIXME: should be: optional long offset = 0  http://crbug.com/258153
     // We mark offset as optional, defaulting to 0; this differs from spec.
     // http://crbug.com/384966
     [RaisesException, TypeChecking=Interface] void extend(Node node, optional long offset);
 
-    [RaisesException] void selectAllChildren([Default=Undefined] optional Node node);
+    [RaisesException] void selectAllChildren(optional Node node);
     [CustomElementCallbacks] void deleteFromDocument();
 
     readonly attribute long rangeCount;
-    [RaisesException] Range getRangeAt([Default=Undefined] optional long index);
-    void addRange([Default=Undefined] optional Range range);
+    [RaisesException] Range getRangeAt(optional long index);
+    void addRange(optional Range range);
     void removeAllRanges();
 
     [NotEnumerable] stringifier;
 
     // Firefox extensions
     // https://developer.mozilla.org/En/DOM/Selection
     //
     // FIXME: Add use counters.
-    boolean containsNode([Default = Undefined] optional Node node, [Default = Undefined] optional boolean allowPartial);
+    boolean containsNode(optional Node node, optional boolean allowPartial = false);
 
     // WebKit extensions
     [MeasureAs=SelectionBaseNode] readonly attribute Node baseNode;
     [MeasureAs=SelectionBaseOffset] readonly attribute long baseOffset;
     [MeasureAs=SelectionExtentNode] readonly attribute Node extentNode;
     [MeasureAs=SelectionExtentOffset] readonly attribute long extentOffset;
 
     // WebKit's "type" accessor returns "None", "Range" and "Caret"
     // IE's type accessor returns "none", "text" and "control"
     [MeasureAs=SelectionType] readonly attribute DOMString type;
 
-    [MeasureAs=SelectionModify] void modify([Default=Undefined] optional DOMString alter,
-                                            [Default=Undefined] optional DOMString direction,
-                                            [Default=Undefined] optional DOMString granularity);
-    [MeasureAs=SelectionSetBaseAndExtent, RaisesException] void setBaseAndExtent([Default=Undefined] optional Node baseNode,
-                                                                                 [Default=Undefined] optional long baseOffset,
-                                                                                 [Default=Undefined] optional Node extentNode,
-                                                                                 [Default=Undefined] optional long extentOffset);
+    [MeasureAs=SelectionModify] void modify(optional DOMString alter,
+                                            optional DOMString direction,
+                                            optional DOMString granularity);
+    [MeasureAs=SelectionSetBaseAndExtent, RaisesException] void setBaseAndExtent(optional Node baseNode,
+                                                                                 optional long baseOffset,
+                                                                                 optional Node extentNode,
+                                                                                 optional long extentOffset);
     [ImplementedAs=collapse, MeasureAs=SelectionSetPosition, RaisesException, TypeChecking=Interface] void setPosition(Node node,
                                                                                                                        optional long offset);
 
     // IE extensions
     // http://msdn.microsoft.com/en-us/library/ms535869(VS.85).aspx
     [MeasureAs=SelectionEmpty] void empty();
 };