docs: private String getActivityInstanceId(PvmExecutionImpl targetScope) {
      if (targetScope.isConcurrent()) {
        return targetScope.getActivityInstanceId();
      } else {
        ActivityImpl targetActivity = targetScope.getActivity();
        if ((targetActivity != null && targetActivity.getActivities().isEmpty())) {
          return targetScope.getActivityInstanceId();
        } else {
          return targetScope.getParentActivityInstanceId();
        }
      }
    }