MDL-65759 library: Update php-css-parser to 8.3.0

lib/php-css-parser/Value/CSSString.php

@@ -2,6 +2,9 @@
 
 namespace Sabberworm\CSS\Value;
 
+use Sabberworm\CSS\Parsing\ParserState;
+use Sabberworm\CSS\Parsing\SourceException;
+
 class CSSString extends PrimitiveValue {
 
 	private $sString;
@@ -11,6 +14,37 @@ class CSSString extends PrimitiveValue {
 		parent::__construct($iLineNo);
 	}
 
+	public static function parse(ParserState $oParserState) {
+		$sBegin = $oParserState->peek();
+		$sQuote = null;
+		if ($sBegin === "'") {
+			$sQuote = "'";
+		} else if ($sBegin === '"') {
+			$sQuote = '"';
+		}
+		if ($sQuote !== null) {
+			$oParserState->consume($sQuote);
+		}
+		$sResult = "";
+		$sContent = null;
+		if ($sQuote === null) {
+			// Unquoted strings end in whitespace or with braces, brackets, parentheses
+			while (!preg_match('/[\\s{}()<>\\[\\]]/isu', $oParserState->peek())) {
+				$sResult .= $oParserState->parseCharacter(false);
+			}
+		} else {
+			while (!$oParserState->comes($sQuote)) {
+				$sContent = $oParserState->parseCharacter(false);
+				if ($sContent === null) {
+					throw new SourceException("Non-well-formed quoted string {$oParserState->peek(3)}", $oParserState->currentLine());
+				}
+				$sResult .= $sContent;
+			}
+			$oParserState->consume($sQuote);
+		}
+		return new CSSString($sResult, $oParserState->currentLine());
+	}
+
 	public function setString($sString) {
 		$this->sString = $sString;
 	}