@Override
  void processLocally() {
    abortBackupFactory.createAbortBackup(cache).run();
    addToResults(member, Collections.emptySet());
  }
AbortBackupStep overrides addToResults in order to include members with empty persistentIds
(such as the sender).
geode-core/src/main/java/org/apache/geode/internal/cache/backup/AbortBackupStep.java