IDL: make optional arguments (without default) explicit sometimes

Source/core/frame/Window.idl

Index: Source/core/frame/Window.idl
diff --git a/Source/core/frame/Window.idl b/Source/core/frame/Window.idl
index f9f7d3ef98f564fda9bcd7f824220ae0c0668e8d..0f9b90350345bc32ff0c583a57dbcc1127029526 100644
--- a/Source/core/frame/Window.idl
+++ b/Source/core/frame/Window.idl
@@ -73,13 +73,13 @@
     DOMString? prompt(optional DOMString message = "",
                       optional DOMString defaultValue = "");
 
-    boolean find([Default=Undefined] optional DOMString string,
-                 [Default=Undefined] optional boolean caseSensitive,
-                 [Default=Undefined] optional boolean backwards,
-                 [Default=Undefined] optional boolean wrap,
-                 [Default=Undefined] optional boolean wholeWord,
-                 [Default=Undefined] optional boolean searchInFrames,
-                 [Default=Undefined] optional boolean showDialog);
+    boolean find(optional DOMString string,
+                 optional boolean caseSensitive,
+                 optional boolean backwards,
+                 optional boolean wrap,
+                 optional boolean wholeWord,
+                 optional boolean searchInFrames,
+                 optional boolean showDialog);
 
     [Replaceable, MeasureAs=WindowOffscreenBuffering] readonly attribute boolean offscreenBuffering;
 
@@ -104,10 +104,10 @@
     [RuntimeEnabled=CSSOMSmoothScroll, RaisesException] void scrollTo(long x, long y, Dictionary scrollOptions);
     void scroll(long x, long y);
     [RuntimeEnabled=CSSOMSmoothScroll, RaisesException] void scroll(long x, long y, Dictionary scrollOptions);
-    void moveBy([Default=Undefined] optional float x, [Default=Undefined] optional float y); // FIXME: this should take longs not floats.
-    void moveTo([Default=Undefined] optional float x, [Default=Undefined] optional float y); // FIXME: this should take longs not floats.
-    void resizeBy([Default=Undefined] optional float x, [Default=Undefined] optional float y); // FIXME: this should take longs not floats.
-    void resizeTo([Default=Undefined] optional float width, [Default=Undefined] optional float height); // FIXME: this should take longs not floats.
+    void moveBy(optional float x, optional float y); // FIXME: this should take longs not floats.
+    void moveTo(optional float x, optional float y); // FIXME: this should take longs not floats.
+    void resizeBy(optional float x, optional float y); // FIXME: this should take longs not floats.
+    void resizeTo(optional float width, optional float height); // FIXME: this should take longs not floats.
 
     [DoNotCheckSecurity] readonly attribute boolean closed;
 
@@ -139,12 +139,12 @@
     readonly attribute StyleMedia styleMedia;
 
     // DOM Level 2 Style Interface
-    CSSStyleDeclaration getComputedStyle([Default=Undefined] optional Element element,
-                                         [TreatUndefinedAs=NullString, Default=Undefined] optional DOMString? pseudoElement);
+    CSSStyleDeclaration getComputedStyle(optional Element element,
+                                         [TreatUndefinedAs=NullString] optional DOMString? pseudoElement);
 
     // WebKit extensions
-    [MeasureAs=GetMatchedCSSRules] CSSRuleList getMatchedCSSRules([Default=Undefined] optional Element element,
-                                                                  [TreatUndefinedAs=NullString, Default=Undefined] optional DOMString? pseudoElement);
+    [MeasureAs=GetMatchedCSSRules] CSSRuleList getMatchedCSSRules(optional Element element,
+                                                                  [TreatUndefinedAs=NullString] optional DOMString? pseudoElement);
 
     [Replaceable] readonly attribute double devicePixelRatio;