Update HTMLFormControlsCollection's named getter to behave according to spec

Source/bindings/tests/idls/TestInterface.idl

 /*
  * Copyright (C) 2010 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.
  * 2.  Redistributions in binary form must reproduce the above copyright
@@ skipping 18 matching lines @@
 // This IDL file is for testing the bindings code generator and for tracking
 // changes in its ouput.
 [
     ActiveDOMObject,
     Conditional=Condition1|Condition2,
     ConstructorCallWith=ExecutionContext,
     Constructor(DOMString str1, [Default=Undefined] optional DOMString str2),
     RaisesException=Constructor,
     SetWrapperReferenceTo(ReferencedType referencedName),
 ] interface TestInterface {
-    [ImplementedAs=getItem] getter (Node or NodeList) (DOMString name);
+    [ImplementedAs=getItem] getter (Node or NodeList) namedItem(DOMString name);
     [Custom] setter Node (DOMString name, Node value);
 };
 
 TestInterface implements TestImplements;