/** @param removeFirst */
 private ActionPair getRemoveIconActionPair(MindMapNode node, MindIcon icon, boolean removeFirst) {
   int iconIndex =
       removeFirst
           ? IconContainedCondition.iconFirstIndex(node, icon.getName())
           : IconContainedCondition.iconLastIndex(node, icon.getName());
   return iconIndex >= 0 ? getRemoveIconActionPair(node, icon, iconIndex) : null;
 }
 private ActionPair getToggleIconActionPair(MindMapNode node, MindIcon icon) {
   int iconIndex = IconContainedCondition.iconFirstIndex(node, icon.getName());
   if (iconIndex == -1) {
     return getAddLastIconActionPair(node, icon);
   } else {
     return getRemoveIconActionPair(node, icon, iconIndex);
   }
 }