keybase_service_base: check refreshers against the local cache
keybase_service_base: check refreshers against the local cache

Issue: KBFS-2308

keybase/kbfs,keybase/client,keybase/client,keybase/client,keybase/client,keybase/kbfs,keybase/client,keybase/client,keybase/client,keybase/kbfs,keybase/client,keybase/client,keybase/client,keybase/client,keybase/kbfs,keybase/client