HRTB test cases from rust-lang/rust #114
Description
Per this conversation, we should model:
- Functions, closures, and HRTB-trait-objects can implement traits such that validity of associated types is never checked. rust#84533
- HRTB on subtrait unsoundly provides HTRB on supertrait with weaker implied bounds rust#84591
- Unsoundness due to where clauses not checked for well-formedness rust#98117