Database activity 'Location' KML file should not return items with no location values

User story: As someone using the KML file returned from the 'Location' database field, I need it to exclude items with no lat/long values so that I can display a map (Leaflet, ArcGIS, Google Map, or what have you) that doesn't error owing to any blank location values.

Suggestions for acceptance criteria:

Given that I'm accessing the KML file, any database rows containing blank lat/long values are not returned by the KML file

Given I'm viewing the options for the Location field in the database activity, I can choose to exclude any items with blank lat/long values from being returned in the KML file.

Mock up of how this might appear attached.