fixing insert before by manually calculating position

Author: Idrinth

lib/Sabberworm/CSS/Rule/Rule.php

@@ -84,6 +84,11 @@ public function getColNo() {
 		return $this->iColNo;
 	}
 
+	public function setPosition($iLine, $iColumn) {
+		$this->iColNo = $iColumn;
+		$this->iLineNo = $iLine;
+	}
+
 	public function setRule($sRule) {
 		$this->sRule = $sRule;
 	}

lib/Sabberworm/CSS/RuleSet/RuleSet.php

@@ -78,6 +78,7 @@ public function addRule(Rule $oRule, Rule $oSibling = null) {
 			$iSiblingPos = array_search($oSibling, $this->aRules[$sRule], true);
 			if ($iSiblingPos !== false) {
 				$iPosition = $iSiblingPos;
+                                                                        $oRule->setPosition($oSibling->getLineNo(), $oSibling->getColNo() - 1);
 			}
 		}