Retrieves the country name for the given location.
For a `GWEATHER_LOCATION_COUNTRY` location, this is equivalent to [[email protected]_name].
For a `GWEATHER_LOCATION_REGION` and `GWEATHER_LOCATION_WORLD` location, this method will return `NULL`.
For other location levels, this method will find the parent `GWEATHER_LOCATION_COUNTRY` and return its name.
| this |
a Location |
|
the location's country name |