Replace return with resolve

index.bs

@@ -350,7 +350,7 @@ parallel</a>:
 2. Run the <a>request Picture-in-Picture algorithm</a> with |video|.
 3. If the previous step threw an exception, reject |promise| with that
     exception and abort these steps.
-4. Return |promise| with the <a>Picture-in-Picture window</a> associated with
+4. [=/Resolve=] |promise| with the <a>Picture-in-Picture window</a> associated with
     {{pictureInPictureElement}}.
 
 ## Extensions to <code>Document</code> ## {#document-extensions}