discuss the trait_alias feature

[lcnr]

Summary

rust-lang/rfcs#1733 introduces the feature(trait_alias) whose implementation hasn't really seen any updates during the last 2 years.

Discuss whether and how we want to support them. Alternatively, we can just keep this as S-types-deferred for now.

edit: I have to admit that I somewhat misunderstood the feature as afaict trait Foo = Bar + Baz really just defines a new name Foo which can be used in bounds and expands to Bar + Baz. So looking at it this way, t-types shouldn't own this feature at all.