getRestrictions
The app user role ids this location is restricted to, if any.
Only populated for locations delivered while user roles are applied via applyUserRoles. Locations restricted to roles that are not applied are not loaded by the SDK at all, so a location that is present is always accessible to the current roles. A location that inherits its restriction from its type carries no value here. Unrelated to getRestrictions, which holds route avoids.
Return
An array of app user role ids (getKey), or null or an empty array if the location carries no restriction of its own