Sema: validate extern struct field types earlier

`validateExternType` does not require the type to be resolved so we can
check it earlier. Only doing it in `resolveTypeFully` lead to worse or
missing compile errors.
794beafb9cVeikka Tuominen committed on 7/21/2022, 7:21:30 PM· committed by Andrew Kelleyparent821e406
8 files changedLine totals unavailable