[css-text-3] export ‘preserved white space’

Author: fantasai

css-text-3/Overview.bs

@@ -820,7 +820,7 @@ Text Processing</h3>
   </dl>
 
   <p>[=White space=] that was not removed or collapsed due to white space processing
-    is called <dfn local-lt="preserved">preserved white space</dfn>.
+    is called <dfn export local-lt="preserved">preserved white space</dfn>.
     In general, <a>preserved white space</a> is measured when calculating
     the intrinsic sizes ([=min-content size=] and [=max-content size=]) of text;
     however <a>preserved white space</a>