Fix button activation steps to reference variable rather than this

Author: lukewarlow

source

@@ -56315,7 +56315,7 @@ interface <dfn interface>HTMLButtonElement</dfn> : <span>HTMLElement</span> {
        <li><p>If the result of running <span>check popover validity</span> given
        <var>target</var>, false, false, and null is true, then run the
        <span data-x="show popover">show popover algorithm</span> given <var>target</var>, false, and
-       <span>this</span>.</p></li>
+       <var>element</var>.</p></li>
 
        <li><p>Otherwise, if the result of running <span>check popover validity</span> given
        <var>target</var>, true, false, and null is true, then run the
@@ -56332,7 +56332,7 @@ interface <dfn interface>HTMLButtonElement</dfn> : <span>HTMLElement</span> {
        <li><p>If the result of running <span>check popover validity</span> given <var>target</var>,
        false, false, and null is true, then run the <span
        data-x="show popover">show popover algorithm</span> given <var>target</var>, false, and
-       <span>this</span>.</p></li>
+       <var>element</var>.</p></li>
       </ol>
      </li>