kbfs_ops: with self-writes, no longer need to special-case public
kbfs_ops: with self-writes, no longer need to special-case public

Issue: KBFS-3080

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