Ensure vt scope qualifies for layout containment (#14327)

Author: vmpstr

css-view-transitions-2/Overview.bs

@@ -632,9 +632,13 @@ Note: An <code>element.startViewTransition()</code> call does not update
 			to |callbackOptions|'s {{StartViewTransitionOptions/update}}.
 
 		1. If [=this=]'s [=principal box=] is [=element-not-rendered|not rendered=],
+			or is an <a spec="css-display-3">internal table box</a> other than ''display/table-cell'',
 			or is an <a spec="css-display-3">internal ruby box</a>
 			or a <a spec="css-display-3" lt="atomic inline">non-atomic</a> <a spec="css-display-3">inline-level</a> box,
-			[=Skip the view transition|skip=] |viewTransition| with an "{{InvalidStateError}}" {{DOMException}}.
+			then [=skip the view transition|skip=] |viewTransition| with an "{{InvalidStateError}}" {{DOMException}},
+			and return |viewTransition|.
+
+			Note: This ensures that [=this=] has a [=principal box=] and qualifies for [=layout containment=].
 
 		1. If [=this=] is not the [=/root element|document root element=],
 			force [=this=] to have both [=layout containment=] and [=view transition scoping=] for the duration of the transition.
@@ -1152,7 +1156,8 @@ and by applying ''view-transition-group'' to the internal element referencing th
 	than the rest of the document.)
 
 	In order to host a [=scoped view transition=],
-	an element must have [=layout containment=],
+	an element must qualify for [=layout containment=],
+	which will be applied automatically,
 	so its painted output can be captured as an atomic unit.
 
 	[=View transitions=] whose [=ViewTransition/root element=] is the [=document element=]