MDL-55224 core: Import PHP-CSS-Parser into core

Part of MDL-55071

lib/php-css-parser/Property/Charset.php

@@ -0,0 +1,66 @@
+<?php
+
+namespace Sabberworm\CSS\Property;
+
+/**
+ * Class representing an @charset rule.
+ * The following restrictions apply:
+ * • May not be found in any CSSList other than the Document.
+ * • May only appear at the very top of a Document’s contents.
+ * • Must not appear more than once.
+ */
+class Charset implements AtRule {
+
+	private $sCharset;
+	protected $iLineNo;
+	protected $aComment;
+
+	public function __construct($sCharset, $iLineNo = 0) {
+		$this->sCharset = $sCharset;
+		$this->iLineNo = $iLineNo;
+		$this->aComments = array();
+	}
+
+	/**
+	 * @return int
+	 */
+	public function getLineNo() {
+		return $this->iLineNo;
+	}
+
+	public function setCharset($sCharset) {
+		$this->sCharset = $sCharset;
+	}
+
+	public function getCharset() {
+		return $this->sCharset;
+	}
+
+	public function __toString() {
+		return $this->render(new \Sabberworm\CSS\OutputFormat());
+	}
+
+	public function render(\Sabberworm\CSS\OutputFormat $oOutputFormat) {
+		return "@charset {$this->sCharset->render($oOutputFormat)};";
+	}
+
+	public function atRuleName() {
+		return 'charset';
+	}
+
+	public function atRuleArgs() {
+		return $this->sCharset;
+	}
+
+	public function addComments(array $aComments) {
+		$this->aComments = array_merge($this->aComments, $aComments);
+	}
+
+	public function getComments() {
+		return $this->aComments;
+	}
+
+	public function setComments(array $aComments) {
+		$this->aComments = $aComments;
+	}
+}