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