@Override
  public @NotNull DomExtension registerCustomChildrenExtension(@NotNull Type type,
                                                               @NotNull CustomDomChildrenDescription.AttributeDescriptor attributeDescriptor) {

    DomExtensionImpl extension = addExtension(myCustoms, null, type);
    extension.setAttributesDescriptor(attributeDescriptor);
    return extension;
  }
@Override
  public @NotNull DomExtension registerCustomChildrenExtension(@NotNull Type type,
                                                               @NotNull CustomDomChildrenDescription.AttributeDescriptor attributeDescriptor)