Geocode provider should not fallback to mapping provider?

In Civi's settings you can choose a 'mapping' provider, but leave a 'geocoding' provider.

This is desirable if you don't want to geocode addresses.

However, if a geocoding provider is not set, CiviCRM falls back to using the 'mapping' provider for Geocoding:

  public static function getProviderClass() {
    $settings = Civi::settings();
    if ($settings->get('geoProvider')) {
      return 'CRM_Utils_Geocode_' . $settings->get('geoProvider');
    }
    elseif ($settings->get('mapProvider')) {
      return 'CRM_Utils_Geocode_' . $settings->get('mapProvider');
    }
    else {
      return '';
    }
  }

This is not the expected behaviour. Admittedly it doesn't make sense to use mapping without geocoding, since you wouldn't have anything to display on the map.

I could make a quick PR to remove the fallback, or we could change the UI to be clearer that rather than 'setting a geocoding provider' it will use mapping as the default, but can be overridden.