Correct popover IDL

Author: annevk

source

@@ -11160,9 +11160,9 @@ interface <dfn interface>HTMLElement</dfn> : <span>Element</span> {
   <span>ElementInternals</span> <span data-x="dom-attachInternals">attachInternals</span>();
 
   // The popover API
-  void <span data-x="dom-showPopover">showPopover</span>();
-  void <span data-x="dom-hidePopover">hidePopover</span>();
-  void <span data-x="dom-togglePopover">togglePopover</span>(optional boolean force);
+  undefined <span data-x="dom-showPopover">showPopover</span>();
+  undefined <span data-x="dom-hidePopover">hidePopover</span>();
+  undefined <span data-x="dom-togglePopover">togglePopover</span>(optional boolean force);
   [<span>CEReactions</span>] attribute DOMString? <span data-x="dom-popover">popover</span>;
 };