docs: public void dumpTo(AreaTree tree, PrintWriter out)
      {
          if (produceHeader)
              out.println("<?xml version=\"1.0\"?>");
          out.println("<areaTree base=\"" + HTMLEntities(tree.getRoot().getPage().getSourceURL().toString()) + "\">");
          recursiveDump(tree.getRoot(), 1, out);
          out.println("</areaTree>");
      }