[css-display] Export 'flow layout'.

Author: tabatkins

css-display-3/Overview.bs

@@ -361,7 +361,7 @@ Inner Display Layout Models: the ''flow'', ''flow-root'', ''table'', ''flex'', '
 	<dl dfn-type="value" dfn-for="display, <display-inside>">
 		<dt><dfn>flow</dfn>
 		<dd>
-			The element lays out its contents using <dfn dfn for>flow layout</dfn>
+			The element lays out its contents using <dfn dfn for export>flow layout</dfn>
 			(<a href="https://www.w3.org/TR/CSS2/visuren.html">block-and-inline layout</a>).
 
 			If its <a>outer display type</a> is ''inline'' or ''run-in'',