[BUGFIX] Improve guard check when getting managed languages

Change-Id: I451ffbd20dacc991576a0073966585224c5d49c0

Author: botweb

Classes/SolrService.php

@@ -565,7 +565,7 @@ protected function getManagedLanguage() {
 
 		$schema = $this->getSchema();
 
-		if (!is_null($schema) && isset($schema->fieldTypes)) {
+		if (is_object($schema) && isset($schema->fieldTypes)) {
 			foreach ($schema->fieldTypes as $fieldType) {
 				if ($fieldType->name === 'text') {
 					foreach ($fieldType->indexAnalyzer->filters as $filter) {