Get rid of custom code for HTMLDocument.write() / writeln()

Source/core/html/HTMLDocument.idl

Index: Source/core/html/HTMLDocument.idl
diff --git a/Source/core/html/HTMLDocument.idl b/Source/core/html/HTMLDocument.idl
index 637318546f9396f7e755242844140f106e37d747..02dea0034ddad84af9c4bbcc038beadefe69ba7b 100644
--- a/Source/core/html/HTMLDocument.idl
+++ b/Source/core/html/HTMLDocument.idl
@@ -21,8 +21,12 @@
 interface HTMLDocument : Document {
     [Custom, CustomElementCallbacks] void open();
     void close();
-    [Custom, PerWorldBindings, ActivityLogging=ForIsolatedWorlds, CustomElementCallbacks] void write([Default=Undefined] optional DOMString text);
-    [Custom, PerWorldBindings, ActivityLogging=ForIsolatedWorlds, CustomElementCallbacks] void writeln([Default=Undefined] optional DOMString text);
+
+    // We support multiple DOMString arguments to match FF / IE, e.g.:
+    // document.write("a", "b", "c") --> document.write("abc")
+    // document.write() --> document.write("")
+    [CallWith=ActiveWindow, PerWorldBindings, ActivityLogging=ForIsolatedWorlds, CustomElementCallbacks] void write(DOMString... text);
+    [CallWith=ActiveWindow, PerWorldBindings, ActivityLogging=ForIsolatedWorlds, CustomElementCallbacks] void writeln(DOMString... text);
 
     readonly attribute HTMLCollection embeds;
     readonly attribute HTMLCollection plugins;