[css-syntax] Require to start with an <ident-token> in Parse a declaration.

Author: SimonSapin

css-syntax/Overview.html

@@ -54,7 +54,7 @@
 </p>
   <h1 class="p-name no-ref" id=title>CSS Syntax Module Level 3</h1>
   <h2 class="no-num no-toc no-ref heading settled heading" id=subtitle><span class=content>Editor’s Draft,
-    <span class=dt-updated><span class=value-title title=20131202>2 December 2013</span></span></span></h2>
+    <span class=dt-updated><span class=value-title title=20131209>9 December 2013</span></span></span></h2>
   <div data-fill-with=spec-metadata><dl><dt>This version:<dd><a class=u-url href=http://dev.w3.org/csswg/css-syntax/>http://dev.w3.org/csswg/css-syntax/</a><dt>Latest version:<dd><a href=http://www.w3.org/TR/css-syntax-3/>http://www.w3.org/TR/css-syntax-3/</a><dt>Editor’s Draft:<dd><a href=http://dev.w3.org/csswg/css-syntax/>http://dev.w3.org/csswg/css-syntax/</a><dt>Previous Versions:<dd><a href=http://www.w3.org/TR/2013/WD-css-syntax-3-20131105/ rel=previous>http://www.w3.org/TR/2013/WD-css-syntax-3-20131105/</a><dd><a href=http://www.w3.org/TR/2013/WD-css-syntax-3-20130919/ rel=previous>http://www.w3.org/TR/2013/WD-css-syntax-3-20130919/</a>
     <dt>Feedback:</dt>
         <dd><a href="mailto:www-style@w3.org?subject=%5Bcss-syntax%5D%20feedback">www-style@w3.org</a>
@@ -3696,6 +3696,10 @@ <h4 class="heading settled heading" data-level=5.3.4 id=parse-a-declaration><spa
 			While the <a data-link-type=dfn href=#current-input-token title="current input token">current input token</a> is a <a class="production css-code" data-link-type=type href=#typedef-whitespace-token title="<whitespace-token>">&lt;whitespace-token&gt;</a>,
 			<a data-link-type=dfn href=#consume-the-next-input-token title="consume the next input token">consume the next input token</a>.
 
+		<li>
+			If the <a data-link-type=dfn href=#current-input-token title="current input token">current input token</a> is not an <a class="production css-code" data-link-type=type href=#typedef-ident-token title="<ident-token>">&lt;ident-token&gt;</a>,
+			return a syntax error.
+
 		<li>
 			<a data-link-type=dfn href=#consume-a-declaration0 title="consume a declaration">Consume a declaration</a>.
 			If anything was returned, return it.

css-syntax/Overview.src.html

@@ -2200,6 +2200,10 @@ <h4 id="parse-a-declaration">
 			While the <a>current input token</a> is a <<whitespace-token>>,
 			<a>consume the next input token</a>.
 
+		<li>
+			If the <a>current input token</a> is not an <<ident-token>>,
+			return a syntax error.
+
 		<li>
 			<a>Consume a declaration</a>.
 			If anything was returned, return it.