IBX-8492: Fixed replacing only field of Content Type with virtual field

Author: Nattfarinn

eZ/Publish/Core/Persistence/Legacy/Content/Mapper.php

@@ -313,9 +313,10 @@ private function buildContentObjects(
                 $content->versionInfo = $versionInfo;
                 $content->versionInfo->names = $names;
                 $content->versionInfo->contentInfo = $contentInfo;
-                $content->fields = array_values($fields[$contentId][$versionId]);
+                $content->fields = array_values($fields[$contentId][$versionId] ?? []);
+
+                $missingVersionFieldDefinitions = $missingFieldDefinitions[$contentId][$versionId] ?? [];
 
-                $missingVersionFieldDefinitions = $missingFieldDefinitions[$contentId][$versionId];
                 foreach ($missingVersionFieldDefinitions as $languageCode => $versionFieldDefinitions) {
                     foreach ($versionFieldDefinitions as $fieldDefinition) {
                         $event = $this->eventDispatcher->dispatch(