Also assert against dangling references after resolving typerefs and processing replacements
Also assert against dangling references after resolving typerefs and processing replacements

Because these operations mutate the IR graph, its better to be safe and double
check again. Don't worry -- these checks only happen on
`testing_only_extra_assertions` builds!

rust-lang/rust-bindgen,rust-lang/rust-bindgen,emilio/rust-bindgen,rust-lang/rust-bindgen,emilio/rust-bindgen,emilio/rust-bindgen,rust-lang/rust-bindgen,emilio/rust-bindgen,emilio/rust-bindgen