title: Specify parent component for a facet to render header within dialog component
body: <p>How to specify the parent component for <code>f:facet</code> to assign it as a child of a <code>p:dialog</code> component ? I've been trying out this but no header is rendered.</p>
  
  <pre><code>&lt;p:dialog id="pageDialog"&gt;
      &lt;p:outputPanel&gt;
          &lt;p:outputPanel&gt;
              &lt;f:facet name="header" parent="pageDialog" &gt;
                  Followed Topics
              &lt;/f:facet&gt;
          &lt;/p:outputPanel&gt;
      &lt;/p:outputPanel&gt;
  &lt;/p:dialog&gt;
  </code></pre>