@Override
  public @NotNull StructureViewTreeElement getRoot() {
    XmlFile myFile = getPsiFile();
    final DomFileElement<DomElement> fileElement = DomManager.getDomManager(myFile.getProject()).getFileElement(myFile, DomElement.class);
    return fileElement == null?
           new XmlFileTreeElement(myFile) :
           new DomStructureTreeElement(fileElement.getRootElement().createStableCopy(), myDescriptor, myNavigationProvider);
  }
@Override
  public @NotNull StructureViewTreeElement getRoot()