Update::checkStage

public function checkStage(): Result
{
	$result = new Result();

	if($this->item->isChanged('STAGE_ID'))
	{
		$userPermissions = Driver::getInstance()->getUserPermissions($this->userId);
		if(!$userPermissions->canMoveItem($this->item, $this->item->remindActualStageId(), $this->item->getStageId()))
		{
			$result->addError($this->getWrongStageError($this->item->getStage()->getName()));
		}
	}

	return $result;
}