@VisibleForTesting
  public List<ID> getMembers() {
    if (view != null) {
      return new ArrayList<>(view.getMembers());
    }
    synchronized (registrants) {
      return new ArrayList<>(registrants);
    }
  }
Called initially and after each auto-reconnect. See restart handlers in InternalLocator
up in geode-core. Services must be started before this call.
geode-membership/src/main/java/org/apache/geode/distributed/internal/membership/gms/locator/GMSLocator.java