[css-syntax] Make url(<ws>*<eof> valid, per EOF-handling rules.

Considering:

* url(<ws>*) is valid (same as url(""))
* url(a<eof> is valid per the "Close open constructs at EOF" rule

Make url(<ws>*<eof> valid too (same as url("")), which is more consistent.

Author: SimonSapin

css-syntax/Overview.html

@@ -11,7 +11,7 @@
 
   <meta content="CSS Syntax Module Level 3 (CSS3 Syntax)" name=dcterms.title>
   <meta content=text name=dcterms.type>
-  <meta content=2013-06-21 name=dcterms.date>
+  <meta content=2013-06-24 name=dcterms.date>
   <meta content="Tab Atkins Jr." name=dcterms.creator>
   <meta content="Simon Sapin" name=dcterms.creator>
   <meta content=W3C name=dcterms.publisher>
@@ -33,7 +33,7 @@
    <h1 class=p-name>CSS Syntax Module Level 3</h1>
 
    <h2 class="no-num no-toc" id=longstatus-date>Editor's Draft <time
-    class=dt-updated datetime=20130621>21 June 2013</time></h2>
+    class=dt-updated datetime=20130624>24 June 2013</time></h2>
 
    <dl>
     <dt>This version:
@@ -1870,7 +1870,7 @@ <h4 id=consume-a-url-token><span class=secno>4.3.5. </span> <dfn
     possible.
 
    <li> If the <a href="#next-input-character"><i>next input
-    character</i></a> is EOF, create a 〈bad-url〉 and return it.
+    character</i></a> is EOF, return the 〈url〉.
 
    <li> If the <a href="#next-input-character"><i>next input
     character</i></a> is a U+0022 QUOTATION MARK (") or U+0027 APOSTROPHE

css-syntax/Overview.src.html

@@ -1138,7 +1138,7 @@ <h4>
 
 		<li>
 			If the <i>next input character</i> is EOF,
-			create a 〈bad-url〉 and return it.
+			return the 〈url〉.
 
 		<li>
 			If the <i>next input character</i> is a U+0022 QUOTATION MARK (") or U+0027 APOSTROPHE (&apos;),