@Override
      public NodeDescriptor<?> @NotNull [] getChildElements(@NotNull Object element) {
        NodeDescriptor<?> nodeDescriptor = (NodeDescriptor<?>)element;
        if (!myCache.containsKey(nodeDescriptor)) {
          myCache.put(nodeDescriptor, treePopupFactory.createChildElements(project, nodeDescriptor));
        }
        return myCache.get(nodeDescriptor);
      }
@Override
      public NodeDescriptor<?> @NotNull [] getChildElements(@NotNull Object element)