code: protected void addClassRow(ClassDoc usedClass, String packageName,
              Content contentTree) {
          DocPath dp = pathString(usedClass,
                  DocPaths.CLASS_USE.resolve(DocPath.forName(usedClass)));
          Content td = HtmlTree.TD(HtmlStyle.colOne,
                  getHyperLink(dp.fragment(packageName), new StringContent(usedClass.name())));
          addIndexComment(usedClass, td);
          contentTree.addContent(td);
      }
docs: Add a row for the class that uses the given package.
  
  @param usedClass the class that uses the given package
  @param packageName the name of the package to which the class belongs
  @param contentTree the content tree to which the row will be added