The alternative to "setReturnRawQueryResult" function, that returns array instead of QueryResultInterface is
$query->execute(TRUE);
Example
public function myFucntion() {
$query = $this->createQuery();
$query->getQuerySettings()->setReturnRawQueryResult(TRUE);
return $query->execute();
}
Becomes
public function myFucntion() {
$query = $this->createQuery();
return $query->execute(TRUE);
}