Define FrameRequestCallback

Fixes https://www.w3.org/Bugs/Public/show_bug.cgi?id=29026

source

@@ -3117,7 +3117,8 @@ a.setAttribute('href', 'http://example.com/'); // change the content attribute d
     </ul>
 
     <p>The <cite>High Resolution Time</cite> specification provides the
-    <dfn><code>Performance</code></dfn> object's <dfn><code data-x="dom-Performance-now"
+    <dfn><code>DOMHighResTimeStamp</code></dfn> typedef and the <dfn><code>Performance</code></dfn>
+    object's <dfn><code data-x="dom-Performance-now"
     data-x-href="http://www.w3.org/TR/hr-time/#dom-performance-now">now()</code></dfn> method. <ref
     spec=HRT></p>
 
@@ -77683,7 +77684,9 @@ dictionary <dfn>DragEventInit</dfn> : <span>MouseEventInit</span> {
   void <span data-x="dom-window-postMessage">postMessage</span>(any message, DOMString targetOrigin, optional sequence&lt;<span>Transferable</span>&gt; transfer);
 };
 <span>Window</span> implements <span>GlobalEventHandlers</span>;
-<span>Window</span> implements <span>WindowEventHandlers</span>;</pre>
+<span>Window</span> implements <span>WindowEventHandlers</span>;
+
+callback <dfn>FrameRequestCallback</dfn> = void (<span>DOMHighResTimeStamp</span> time);</pre>
 
 <!-- for more features to add here, look here:
  http://msdn.microsoft.com/workshop/author/dhtml/reference/objects/obj_window.asp