[css-font-loading] Move source argument parsing to the sync section, when it's a string.

Author: tabatkins

css-font-loading/Overview.bs

@@ -213,26 +213,14 @@ The Constructor</h3>
 		Parse the {{family!!argument}} argument,
 		and the members of the {{descriptors!!argument}} argument,
 		according to the grammars of the corresponding descriptors of the CSS ''@font-face'' rule.
+		If the {{source!!argument}} argument is a {{DOMString}},
+		parse it according to the grammar of the CSS ''@font-face/src'' descriptor of the ''@font-face'' rule.
 		If any of them fail to parse correctly,
 		reject <var>font face's</var> {{[[FontStatusPromise]]}} with a DOMException named "SyntaxError",
 		set <var>font face’s</var> corresponding attributes to the empty string,
 		and set <var>font face’s</var> {{FontFace/status}} attribute to "error".
 		Otherwise, set <var>font face's</var> corresponding attributes to the serialization of the parsed values.
 
-		Return <var>font face</var>.
-		If <var>font face’s</var> {{FontFace/status}} is "error",
-		terminate this algorithm;
-		otherwise,
-		complete the rest of these steps asynchronously.
-
-	2. If the {{source!!argument}} argument was a {{DOMString}},
-		parse it according to the grammar of the 'src' descriptor of the CSS ''@font-face'' rule.
-		If it fails to parse correctly,
-		queue a task to set <var>font face’s</var> {{FontFace/status}} attribute to "error"
-		and reject <var>font face's</var> {{[[FontStatusPromise]]}} with a DOMException named "SyntaxError" exception,
-		and abort these steps;
-		otherwise, set <var>font face's</var> internal {{[[Urls]]}} slot to the string.
-
 		Note: Note that this means that passing a naked url as the source argument,
 		like <code>"http://example.com/myFont.woff"</code>,
 		won't work - it needs to be at least wrapped in a ''url()'' function,
@@ -249,6 +237,15 @@ The Constructor</h3>
 		or should they use their worker url?
 		Is that always defined?
 
+		Return <var>font face</var>.
+		If <var>font face’s</var> {{FontFace/status}} is "error",
+		terminate this algorithm;
+		otherwise,
+		complete the rest of these steps asynchronously.
+
+	2. If the {{source!!argument}} argument was a {{DOMString}},
+		set <var>font face's</var> internal {{[[Urls]]}} slot to the string.
+
 		If the {{source}} argument was a {{BinaryData}},
 		set <var>font face's</var> internal {{[[Data]]}} slot to the passed argument.