Changes from #14579
Changes from #14579

We now have a top-level `tyConAppNeedsKindSig` function, which means
that we can delete lots of code in `Convert`.

(cherry picked from commit cfd682c5fd03b099a3d78c44f9279faf56a0ac70)

haskell/haddock,haskell/haddock,haskell/haddock,haskell/haddock,haskell/haddock