Remove manual custom element upgrade

dom.bs

@@ -2982,19 +2982,10 @@ before a <var>child</var>, run these steps:
     <a>insertion steps</a> or <a>removing steps</a> for <var>inclusiveDescendant</var>.
    </li>
 
-   <p>If <var>inclusiveDescendant</var> is <a for=Element>custom</a> and <var>newParent</var> is
+   <li><p>If <var>inclusiveDescendant</var> is <a for=Element>custom</a> and <var>newParent</var> is
    <a>connected</a>, then <a>enqueue a custom element callback reaction</a> with
    <var>inclusiveDescendant</var>, callback name "<code>connectedMoveCallback</code>", and an empty
    argument list.
-
-   <li>
-    <p>Otherwise, <a lt="try to upgrade an element">try to upgrade</a>
-    <var>inclusiveDescendant</var>.
-
-    <p class=note>If this successfully upgrades <var>inclusiveDescendant</var>, its
-    <code>connectedCallback</code> will be enqueued automatically during the
-    <a>upgrade an element</a> algorithm.
-   </li>
   </ol>
  </li>