Make beforeMarhal $options an ArrayObject.

Use consistent types across the various event methods.

Refs #5711

src/ORM/Marshaller.php

@@ -198,6 +198,7 @@ protected function _prepareData($data, $options)
         }
 
         $dataObject = new \ArrayObject($data);
+        $options = new \ArrayObject($options);
         $this->_table->dispatchEvent('Model.beforeMarshal', compact('dataObject', 'options'));
 
         return (array)$dataObject;