[O] [BUG] org-html export does not put section numbers in div id

[Matt Lundin]

Take the following file:

--8<---------------cut here---------------start------------->8---
#+options: num:nil

* Headline
** Subheading
* Another headline
--8<---------------cut here---------------end--------------->8---

When exported to html, the section headings are not numbered, as
expected. 

However, the section numbers are missing from the outline container
divs, which look like this:

<div id="outline-container-sec-" class="outline-2">

As a result, the table of contents links do not work.

Here are the relevant portions of the html:

--8<---------------cut here---------------start------------->8---
<div id="content">
<h1 class="title">test</h1>
<div id="table-of-contents">
<h2>Table of Contents</h2>
<div id="text-table-of-contents">
<ul>
<li><a href="#sec-1">Headline</a>
<ul>
<li><a href="#sec-1-1">Subheading</a></li>
</ul>
</li>
<li><a href="#sec-2">Another headline</a></li>
</ul>
</div>
</div>

<div id="outline-container-sec-" class="outline-2">
<h2 id="sec-">Headline</h2>
<div class="outline-text-2" id="text-1">
</div><div id="outline-container-sec-" class="outline-3">
<h3 id="sec-">Subheading</h3>
</div>
</div>
<div id="outline-container-sec-" class="outline-2">
<h2 id="sec-">Another headline</h2>
</div>
</div>
--8<---------------cut here---------------end--------------->8---

Thanks,
Matt