code: @Override
    public void deleteHistoricIdentityLink(String id) {
      if (isHistoryLevelAtLeast(HistoryLevel.AUDIT)) {
        getHistoricIdentityLinkEntityManager().delete(id);
      }
    }
docs: /*
  (non-Javadoc)
  
  @see org.activiti.engine.impl.history.HistoryManagerInterface# deleteHistoricIdentityLink(java.lang.String)