Add CloseEvent interface for "close" in the Event index

Fixes #4568.

Author: ArfatSalman

source

@@ -121322,7 +121322,7 @@ INSERT INTERFACES HERE
 
     <tr> <!-- close -->
      <td> <dfn data-dfn-type="event" data-dfn-for="HTMLElement,WebSocket" data-export=""><code data-x="event-close">close</code></dfn>
-     <td> <code>Event</code>
+     <td> <code>Event</code> or <code>CloseEvent</code>
      <td> <code>dialog</code> elements, <code>WebSocket</code>
      <td> Fired at <code>dialog</code> elements when they are closed, and at <code>WebSocket</code> elements when the connection is terminated
 
@@ -122338,6 +122338,7 @@ INSERT INTERFACES HERE
   Anthony Ricaud,
   Anton Vayvod,
   Antti Koivisto,
+  Arfat Salman,
   Arkadiusz Michalski,
   Arne Thomassen,
   Aron Spohr,