Redo T7919 and TH_spliceE5_prof with a cabal file
Right now T7919 fails because the new dynamic-by-default GHC means that Template Haskell must be built with dynamic; of course, GHC isn't clever enough to figure this out. If we Cabalize the test, the example should start building again (and if they don't, well, that's a bug!)
TH_spliceE5_prof can also use this treatment.