I am going to leave in the infrastructure around this just in case. But there is
no reason to keep this in the tests themselves. I can always just revert this
and I don't think merge conflicts are likely due to previous work I did around
the tooling for this.
Looking up the conformance @dynamic_self C<T> : P simply returns
the normal conformance C<T> : P.
If we later apply a substitution map to the conformance to
specialize T, we would call isSpecialized() on the substituted
type, which would return false. We would then hit an assertion
because the type type @dynamic_self C<Int> is not equal to the
(erroneously unsubstituted) conformance type C<T>.
Tweak the logic slightly to avoid this.