Task::pin

public function pin($id, $groupId = 0)
{
	if (!TaskAccessController::can($this->userId, ActionDictionary::ACTION_TASK_READ, (int)$id))
	{
		$this->addForbiddenError();
		$result = new UtilResult();
		$result->loadErrors($this->errors);
		return $result;
	}

	$option = UserOptionOption::PINNED;
	$groupId = (int)$groupId;
	if ($groupId)
	{
		$option = UserOptionOption::PINNED_IN_GROUP;
	}
	return UserOption::add($id, UtilUser::getId(), $option);
}