Use ToggleEvent for <details> element toggle event

source

@@ -58902,8 +58902,19 @@ interface <dfn interface>HTMLDetailsElement</dfn> : <span>HTMLElement</span> {
     fired.</p>
    </li>
 
-   <li><p><span data-x="concept-event-fire">Fire an event</span> named <code
-   data-x="event-toggle">toggle</code> at the <code>details</code> element.</p></li>
+   <li><p>If the <code data-x="attr-details-open">open</code> attribute is added, <span
+    data-x="concept-event-fire">fire an event</span> named <code data-x="event-toggle">toggle</code>
+    using <code>ToggleEvent</code>, with the <code data-x="dom-ToggleEvent-oldState">oldState</code>
+    attribute initialized to "<code data-x="">closed</code>", and the <code
+    data-x="dom-ToggleEvent-newState">newState</code> attribute initialized to "<code
+    data-x="">open</code>" at the <code>details</code> element.</p></li>
+
+    <li><p>Otherwise, <span data-x="concept-event-fire">fire an event</span> named <code
+    data-x="event-toggle">toggle</code> using <code>ToggleEvent</code>, with the <code
+    data-x="dom-ToggleEvent-oldState">oldState</code> attribute initialized to "<code
+    data-x="">open</code>", and the <code data-x="dom-ToggleEvent-newState">newState</code>
+    attribute initialized to "<code data-x="">closed</code>" at the <code>details</code>
+    element.</p></li>
   </ol>
 
   <p>The <dfn attribute for="HTMLDetailsElement"><code data-x="dom-details-open">open</code></dfn>
@@ -132164,7 +132175,7 @@ INSERT INTERFACES HERE
 
     <tr> <!-- toggle -->
      <td> <dfn event for="HTMLElement"><code data-x="event-toggle">toggle</code></dfn>
-     <td> <code>Event</code> or <code>ToggleEvent</code>
+     <td> <code>ToggleEvent</code>
      <td> <code>details</code> and <span data-x="attr-popover">popover</span> elements
      <td> Fired at <code>details</code> elements when they open or close; fired on elements with the
      <code data-x="attr-popover">popover</code> attribute when they are transitioning between