Function collect_type_invariants 

fn collect_type_invariants<'tcx>(
    tcx: TyCtxt<'tcx>,
    def_id: DefId,
    db: &HashMap<String, TypeInvariantEntry>,
    type_path: &str,
    param_name: &str,
    results: &mut Vec<Property<'tcx>>,
)

Look up the type path in the DB and add instantiated invariants to results.