@Override
  public List<String> getUrlFor(PsiElement element, PsiElement originalElement) {
    for (DocumentationProvider provider : getAllProviders()) {
      List<String> result = provider.getUrlFor(element, originalElement);
      if (result != null) {
        LOG.debug("getUrlFor: ", provider);
        return result;
      }
    }
    return null;
  }
@Override
  public List<String> getUrlFor(PsiElement element, PsiElement originalElement)