Function recover_infer_ret_ty

fn recover_infer_ret_ty<'tcx>(
    icx: &ItemCtxt<'tcx>,
    infer_ret_ty: &'tcx Ty<'tcx>,
    generics: &'tcx Generics<'tcx>,
    def_id: LocalDefId,
) -> PolyFnSig<'tcx>