title: Mootools add a class to 'a' href="something"
body: <p>The situation is that I want to add a class 'display-none' to li eliment which has a child eliment 'a' </p>
  
  <pre><code>&lt;li class="mostread"&gt;
      &lt;a href="/intranet/Admin/Error-Pages/404.html" class="mostread"&gt;404&lt;/a&gt;
  &lt;/li&gt;
  </code></pre>
  
  <p>i.e.,
  if li class mostread has child element a href="/intranet/Admin/Error-Pages/404.html" and class mostread then add class 'display-none' to the parent li.</p>
  
  <p>After processing it would look like</p>
  
  <pre><code>&lt;li class="mostread display-none"&gt;
      &lt;a href="/intranet/Admin/Error-Pages/404.html" class="mostread"&gt;404&lt;/a&gt;
  &lt;/li&gt;
  </code></pre>