A couple minimal examples that cause the compiler to panic when using associated_type_bounds

https://play.rust-lang.org/?version=nightly&mode=debug&edition=2018&gist=b710f545c85c97f070bb6a907d265da1
https://play.rust-lang.org/?version=nightly&mode=debug&edition=2018&gist=c4f697b2946691a3173aae09399dcc3c

I gotta run, so I can't go into further depth right now. These should probably be split into separate tracking issues