code: private void addIndexLink(DeprecatedAPIListBuilder builder,
              DeprElementKind kind, Content contentTree) {
          if (builder.hasDocumentation(kind)) {
              Content li = HtmlTree.LI(getHyperLink(getAnchorName(kind),
                      contents.getContent(getHeadingKey(kind))));
              contentTree.addContent(li);
          }
      }
docs: Add the index link.
  
  @param builder the deprecated list builder
  @param type the type of list being documented
  @param contentTree the content tree to which the index link will be added