tlf_handle: update FirstResolvedWriter comment
tlf_handle: update FirstResolvedWriter comment

Suggested by songgao.

Issue: #1002

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