the xml test of loggerPrinter.java is down since the online check library is closed #246

@Override public void xml(@Nullable String xml) {
    if (Utils.isEmpty(xml)) {
      d("Empty/Null xml content");
      return;
    }
    try {
      Source xmlInput = new StreamSource(new StringReader(xml));
      StreamResult xmlOutput = new StreamResult(new StringWriter());
      Transformer transformer = TransformerFactory.newInstance().newTransformer();
      transformer.setOutputProperty(OutputKeys.INDENT, "yes");
      transformer.setOutputProperty("{http://xml.apache.org/xslt}indent-amount", "2");
      transformer.transform(xmlInput, xmlOutput);
      d(xmlOutput.getWriter().toString().replaceFirst(">", ">\n"));
    } catch (TransformerException e) {
      e("Invalid xml");
    }
  }