Fix negativ pid when doing a positioned insert

If you insert a content element (or a page) at a concrete position f.e. after content element 15 the value in $row['pid'] is -15.

But in $this->data we already have the real pid, so we can just use it.

Classes/Form/Element/RichTextElement.php

@@ -224,7 +224,7 @@ class RichTextElement extends AbstractFormElement {
 
 		$this->resultArray = $this->initializeResultArray();
 		$this->defaultExtras = BackendUtility::getSpecConfParts($parameterArray['fieldConf']['defaultExtras']);
-		$this->pidOfPageRecord = $table === 'pages' && MathUtility::canBeInterpretedAsInteger($row['uid']) ? (int) $row['uid'] : (int) $row['pid'];
+		$this->pidOfPageRecord = $this->data['effectivePid'];
 		BackendUtility::fixVersioningPid($table, $row);
 		$this->pidOfVersionedMotherRecord = (int) $row['pid'];
 		$this->vanillaRteTsConfig = $backendUser->getTSConfig('RTE', BackendUtility::getPagesTSconfig($this->pidOfPageRecord));