public static @NotNull @Nls String calcPrefix(@Nullable ErrorTreeElement element) {
    if(element instanceof SimpleMessageElement || element instanceof NavigatableMessageElement) {
      String prefix = element.getPresentableText();

      if (element instanceof NavigatableMessageElement) {
        String rendPrefix = ((NavigatableMessageElement)element).getRendererTextPrefix();
        if (!StringUtil.isEmpty(rendPrefix)) prefix += rendPrefix + " ";
      }

      return prefix;
    }
    return "";
  }
public static @NotNull @Nls String calcPrefix(@Nullable ErrorTreeElement element)