protected void calculateRequiredLength(SingleRowPassInfo data) {
    data.requiredLength += tabs.isHorizontalTabs() ? data.insets.left + data.insets.right
                                                   : data.insets.top + data.insets.bottom;
    for (TabInfo eachInfo : data.visibleInfos) {
      data.requiredLength += getRequiredLength(eachInfo);
      data.toLayout.add(eachInfo);
    }
    data.requiredLength += getStrategy().getAdditionalLength(data);
  }
protected void calculateRequiredLength(SingleRowPassInfo data)