[css-cascade-4] Clean up

Author: fantasai

css-cascade-4/Overview.bs

@@ -17,7 +17,6 @@ Previous Version: https://www.w3.org/TR/2015/WD-css-cascade-4-20150421/
 Previous Version: https://www.w3.org/TR/2013/WD-css-cascade-3-20130730/
 Previous Version: https://www.w3.org/TR/2013/WD-css3-cascade-20130103/
 Previous Version: https://www.w3.org/TR/2005/WD-css3-cascade-20051215/
-Issue Tracking: Disposition of Comments https://drafts.csswg.org/css-cascade/issues
 Abstract: This CSS module describes how to collate style rules and assign values to all properties on all elements. By way of cascading and inheritance, values are propagated for all properties on all elements.
 Abstract:
 Abstract: New in this level are the ''revert'' keyword and <<supports-condition>> for the ''@import'' rule.
@@ -747,8 +746,6 @@ Filtering</h2>
 			and the declaration's value matches the syntax for that property.
 	</ul>
 
-	ISSUE: Define whatever it is that Shadow DOM needs here.
-
 	The values of the declarations that apply form,
 	for each property on each element,
 	a list of <a>declared values</a>.