Function late_param_regions_to_bound 

fn late_param_regions_to_bound<'tcx, T>(
    tcx: TyCtxt<'tcx>,
    scope: DefId,
    bound_vars: &'tcx List<BoundVariableKind<'tcx>>,
    value: T,
) -> Binder<'tcx, T>
where
    T: TypeFoldable<TyCtxt<'tcx>>,

Convert ReLateParams in value back into ReBounds and bind it with bound_vars.