[css-scoping-1][editorial] Update changes, see #7494

Author: svgeesus

css-scoping-1/Overview.bs

@@ -803,6 +803,7 @@ Changes</h2>
 	The following significant changes were made since the
 	<a href="https://www.w3.org/TR/2014/WD-css-scoping-1-20140403/">3 April 2014 Working Draft</a>.
 
+	* Defined that tree-scoped names inherit into descendant shadow trees
 	* Renamed <css>::content</css> to ''::slotted''.
 	* Define the flattened tree.
 	* Generally reorg and rebase the Shadow DOM section on top of current DOM.