public Set<ID> getCrashedMembers() {
    return crashedMembers;
  }
This functions returns the list of preferred coordinators. One random member from list of
non-preferred member list. It make sure that random member is not in suspected Set. And local
member.

@param filter Suspect member set.
@param localAddress the address of this member
@param maxNumberDesired number of preferred coordinators to return
@return list of preferred coordinators
geode-membership/src/main/java/org/apache/geode/distributed/internal/membership/gms/GMSMembershipView.java