Rust does not normalize opaque types with escaping bound vars

[compiler-errors]

Opening this issue to record the fact that we don't normalize opaques with escaping bound vars in Reveal::All mode after #103509.

I am not aware of any impacts of this on regular rustc compilation sessions, at least not without using TAIT in some strange ways. However, this causes rust-lang/miri#2433 to reoccur, and makes me sad theoretically, since we should be revealing all opaques during monomorphization, for example.

Fixing this is not hard (43119d6, #100980), but doing it without incurring major performance penalties (#103423) is difficult.

[RalfJung]

FWIW the Miri ICE also needs type_alias_impl_trait.