Bug description:
When bindgen creates bindings to C unions which have typedef aliases, and the default
alias style is TypeAlias, everything works as expected. However, if the default alias style is NewType or NewTypeDeref, and we ask bindgen to derive_debug and impl_debug, then the union will have a Debug implementation but the alias newtype wrapper will not.
Expected behavior: bindgen should create Debug implementations for both the original union and its alias newtype wrapper.
Actual behavior: bindgen creates a Debug implementation only for the union type, and not for its alias newtype wrapper.
The same error is observed for structs which contain unions and have a typedef alias.