Match percent symbol or alphanumeric text

Co-authored-by: Weston Ruter <[email protected]>

Author: pierlon

lib/Sabberworm/CSS/Value/Size.php

@@ -41,7 +41,7 @@ public static function parse(ParserState $oParserState, $bIsColorComponent = fal
 		$aSizeUnits = self::getSizeUnits();
 		$iMaxSizeUnitLength = max(array_keys($aSizeUnits));
 
-		if ( preg_match( '/^[a-zA-Z0-9%]+/', $oParserState->peek($iMaxSizeUnitLength), $matches ) ) {
+		if ( preg_match( '/^(%|[a-zA-Z0-9]+)/', $oParserState->peek($iMaxSizeUnitLength), $matches ) ) {
 			$sUnit = strtolower($matches[0]);
 			$iUnitLength = strlen($sUnit);