[css-syntax-3][editorial] Updated Changes section.

Author: tabatkins

css-syntax-3/Overview.bs

@@ -3780,6 +3780,50 @@ Changes</h2>
 
 	<em>This section is non-normative.</em>
 
+<h3 id="changes-CR-20211224">
+Changes from the 24 December 2021 Candidate Recommendation Draft</h3>
+
+	The following substantive changes were made:
+
+	* The definition of [=non-ASCII code point=]
+		was restricted to omit some potentially troublesome codepoints.
+		(<a href="https://github.com/w3c/csswg-drafts/issues/7129">7129</a>)
+
+	* Defined the <code>&lt;foo()></code> and <code>&lt;@foo></code> productions.
+		(<a href="https://github.com/w3c/csswg-drafts/issues/5728">5728</a>)
+
+	* Allow nested style rules.
+		(<a href="https://github.com/w3c/csswg-drafts/issues/7961#issuecomment-1514955984">7961</a>).
+
+	* As part of allowing Nesting,
+		significantly rewrote the entire parsing section.
+		Notably, removed "parse a list of rules" and "parse a list of declarations"
+		in favor of "parse a stylesheet's contents" and "parse a block's contents".
+		Only additional normative change is that
+		semicolons trigger slightly different error-recovery now
+		in some contexts,
+		so that parsing of things like ''@media'' blocks
+		is identical whether they're nested or not.
+		(<a href="https://github.com/w3c/csswg-drafts/issues/8834">8834</a>).
+
+	* Removed the attempt at a <code>&lt;urange></code> production
+		in terms of existing tokens,
+		instead relying on a special re-parse from source
+		specifically when you're parsing the '@font-face/unicode-range' descriptor.
+		(<a href="https://github.com/w3c/csswg-drafts/issues/8835">8835</a>)
+
+	* Since the above removed the main need to preserve a token's "representation"
+		(the original string it was parsed from),
+		removed the rest of the references to "representation"
+		in the An+B section
+		and instead just recorded the few bits of information necessary for that
+		(whether or not the number had an explicit sign).
+
+	* Explicitly noted that some uses
+		([=custom properties=], the ''@font-face/unicode-range'' descriptor)
+		require access to the original string of a declaration's entire value,
+		and marked where that occurs in the parser.
+
 <h3 id="changes-CR-20190716">
 Changes from the 16 August 2019 Candidate Recommendation</h3>