Is mkTrApp unsafe?

[Andrew Martin]

I've been playing around with the GHC 8.2 release candidate. In
Type.Reflection.Unsafe, there's a really handy function named mkTrApp.
Everything else in that module is pretty evidently unsafe, but I'm not
so sure about mkTrApp. I'm wondering if it should actually be exported
by Type.Reflection instead or if I've missed some way it could be used
to create an ill-kinded TypeRep.

-Andrew Martin