[css-counter-styles-3] Update Changes list

Author: fantasai

css-counter-styles-3/Overview.bs

@@ -2631,10 +2631,35 @@ Sample style sheet for HTML</h2>
 <h2 class='no-num' id='changes'>
 Changes</h2>
 
+<h3 id='changes-2017'>
+Changes since the December 2017 Candidate Recommendation</h3>
+
+	Significant changes since the <a href="https://www.w3.org/TR/2017/CR-css-counter-styles-3-20171214/">December 14 2017 Candidate Recommendation</a>:
+
+	* Made ''none'', ''decimal'', ''disc'', ''circle'', ''square'', ''disclosure-open'', ''disclosure-close'' non-overridable.
+		(<a href="https://github.com/w3c/csswg-drafts/issues/3584">Issue 3584</a>)
+	* Clarified counter-style lookups in Shadow DOM.
+		(<a href="https://github.com/w3c/csswg-drafts/issues/5693">Issue 5693</a>)
+	* Clarified what happens in various invalid ''@counter-style'' situations.
+		(<a href="https://github.com/w3c/csswg-drafts/issues/5698">Issue 5698</a>,
+		 <a href="https://github.com/w3c/csswg-drafts/issues/5717">Issue 5717</a>)
+	* Fixed divide-by-zero error in additive algorithm.
+		(<a href="https://github.com/w3c/csswg-drafts/issues/5784">Issue 5784</a>)
+	* Fixed ''square'' symbol to not use an emoji symbol.
+		(<a href="https://github.com/w3c/csswg-drafts/issues/6200">Issue 6200</a>)
+	* Allowed UAs to override the font choice of predefined symbolic counter styles.
+		(<a href="https://github.com/w3c/csswg-drafts/issues/6201">Issue 6201</a>)
+	* Restricted special rendering of predefined symbolic counter styles to usage as a list marker via 'list-style-type'.
+		(<a href="https://github.com/w3c/csswg-drafts/issues/6201">Issue 6201</a>)
+	* Clarified that 'speak-as' represents spoken output; it may be used for other AT.
+		(<a href="https://github.com/w3c/csswg-drafts/issues/6040">Issue 6040</a>)
+
+	A <a href="https://drafts.csswg.org/css-counter-styles-3/issues-cr-2017">Disposition of Comments</a> is available.
+
 <h3 id='changes-jun-2015'>
-Changes since the Jun 2015 Candidate Recommendation</h3>
+Changes since the June 2015 Candidate Recommendation</h3>
 
-	Significant changes since the <a href="https://www.w3.org/TR/2015/CR-css-counter-styles-3-20150611/">June 11 2015 CR</a> draft:
+	Significant changes since the <a href="https://www.w3.org/TR/2015/CR-css-counter-styles-3-20150611/">June 11 2015 Candidate Recommendation</a>:
 
 	* Exclude "none" and "disc" from being the name of a counter style.
 	* When setting CSSCounterStyle.name, take the string directly; don't [=CSS/parse=] it as an ident.