This is a smoke test for the fuchsia.intl.PropertyProvider protocol implementer (usually intl_services). It also relies on setui_service and that component's implementation of fuchsia.settings.Intl.
This test modifies the user's internationalization preferences but attempts to restore the original values after it runs.
fx set core.x64 --with //sdk/cts/tests/fidl/fuchsia.intl:tests # ... fx test intl-services-system-test