protected function createValueHolderChangedEvent($prev_value, EventInterface $embedded_event = null)
    {
        return new ValueChangedEvent(
            array(
                'attribute_name' => $this->getAttribute()->getName(),
                'prev_value' => $prev_value,
                'value' => $this->toNative(),
                'embedded_event' => $embedded_event
            )
        );
    }