Fix an array access attempt of a null value.

Author: hperrin

src/Drivers/DriverTrait.php

@@ -667,7 +667,7 @@ private function getEntitesRowLike(
           $dataNameAndSValue = $getDataNameAndSValueCallback($row);
           $sdata[$dataNameAndSValue['name']] = $dataNameAndSValue['svalue'];
           $row = $rowFetchCallback($result);
-        } while ($getGUIDCallback($row) === $guid);
+        } while ($row && $getGUIDCallback($row) === $guid);
       } else {
         // Make sure that $row is incremented :)
         $row = $rowFetchCallback($result);