fn is_late_bound_map( tcx: TyCtxt<'_>, owner_id: OwnerId ) -> Option<&FxIndexSet<ItemLocalId>>
Detects late-bound lifetimes and inserts them into
A region declared on a fn is late-bound if:
- it is constrained by an argument type;
- it does not appear in a where-clause.
“Constrained” basically means that it appears in any type but
not amongst the inputs to a projection. In other words,
<&'a T as Trait<''b>>::Foo does not constrain