Livefeed::normalizeFilter

public function normalizeFilter($filter)
{
	if (!is_array($filter))
	{
		return [];
	}
	if (empty($filter))
	{
		return $filter;
	}

	$result = [];
	foreach ($filter as $row)
	{
		if (empty($row) || !is_array($row))
		{
			continue;
		}
		if (empty($row['key']) || empty($row['value']))
		{
			continue;
		}
		$result[] = $row;
	}
	unset($row);

	if (!empty($result))
	{
		MainTypeCollection::sortByColumn($result, ['key' => SORT_ASC]);
	}
	return $result;
}