[css-inline] add font-size to properties not allowed on initial letter per w3c#2700

Author: dauwhe

css-inline-3/Overview.bs

@@ -580,7 +580,7 @@ Properties</h4>
 	(unless it is an <a>atomic inline</a>,
 	in which case the set of properties that apply to an <a>atomic inline</a> apply)
 	except for 'vertical-align' and its <a>sub-properties</a>,
-	and 'line-height'.
+	'font-size', and 'line-height'.
 	<!-- Basically, any properties defined in css-inline
 	except those specific to initial letters,
 	so keep this list updated as we add things to this spec. -->