Make item(undefined) act the same way as item("undefined")

source

@@ -7106,7 +7106,8 @@ interface <dfn>HTMLAllCollection</dfn> {
   readonly attribute unsigned long <span data-x="dom-HTMLAllCollection-length">length</span>;
   getter <span>Element</span>? (unsigned long index);
   getter (<span>HTMLCollection</span> or <span>Element</span>)? <span data-x="dom-HTMLAllCollection-namedItem">namedItem</span>(DOMString name);
-  (<span>HTMLCollection</span> or <span>Element</span>)? <span data-x="dom-HTMLAllCollection-item">item</span>(optional DOMString nameOrIndex);
+  (<span>HTMLCollection</span> or <span>Element</span>)? <span data-x="dom-HTMLAllCollection-item-noargs">item</span>();
+  (<span>HTMLCollection</span> or <span>Element</span>)? <span data-x="dom-HTMLAllCollection-item">item</span>(DOMString nameOrIndex);
 
   // Note: HTMLAllCollection objects have a <a href="#HTMLAllCollection-call">custom [[Call]] internal method</a> in addition to regular
   // Web IDL semantics.
@@ -7170,6 +7171,9 @@ interface <dfn>HTMLAllCollection</dfn> {
   method must return the result of <span data-x="concept-get-all-named">getting the "all"-named
   element(s)</span> from this <code>HTMLAllCollection</code> given <var>name</var>.</p>
 
+  <p>The <dfn><code data-x="dom-HTMLAllCollection-item-noargs">item()</code></dfn> method must return
+  null.</p>
+
   <p>The <dfn><code data-x="dom-HTMLAllCollection-item">item(<var>nameOrIndex</var>)</code></dfn>
   method must return the result of <span data-x="concept-get-all-indexed-or-named">getting the
   "all"-indexed or named element(s)</span> from this <code>HTMLAllCollection</code> given