Simplify BatchChange.IsDraft()
Created by: mrnugget
This is the result of the discussion with @eseliger and @courier-new yesterday.
LastAppliedAt.IsZero()
is the only safe indicator whether something is
a draft, since the user ids (LastApplierID
and InitialApplierID
)
could be 0 after a user is deleted and BatchSpecID
we don't need to
check since it's non-nullable in the DB.