Validation introduced in #113124 allows UnwindAction::Continue and
TerminatorKind::Resume to occur only in functions with ABI that can
unwind. The function ABI depends on the panic strategy, which can vary
across crates.
Usually MIR is built and validated in the same crate. The coroutine drop
glue thus far was an exception. As a result validation could fail when
mixing different panic strategies.
Avoid the problem by executing AbortUnwindingCalls along with the
validation.
