[css-display] List flow/flow-root values as a change.

Author: fantasai

css-display/Overview.bs

@@ -810,9 +810,15 @@ Changes</h2>
 	Changes since the <a href="http://www.w3.org/TR/2014/WD-css-display-3-20140911/">11 September 2014 Working Draft</a> include:
 
 	<ul>
-		<li>Removed <css>display-inside</css>, <css>display-outside</css>, and <css>display-extras</css>,
+		<li>Removed <css>display-inside</css>, <css>display-outside</css>, and <css>display-extras</css> longhands,
 			in favor of just making 'display' multi-value.
 			(This was done to impose constraints on what can be combined.
 			Future levels of this specification may relax some or all of those restrictions
 			if they become unnecessary or unwanted.)
+		<li>Created the ''flow'' and ''flow-root'' <a>inner display types</a>
+			to better express flow layout <a>display types</a>
+			and to create an explicit switch for making an element a <a>BFC</a> root.
+			(This should eliminate the need for hacks
+			like ''::after { clear: both; }'' and ''overflow: hidden''
+			that are intended to accomplish this purpose.)
 	</ul>