title: php domdocument creates self closing tag that breaks html
body: <p>I'm parsing user input text &amp; converting youtube urls into an iframe using a regex so I end up with the following:</p>
  
  <pre><code>&lt;iframe title="YouTube video player" width="640" height="370" src="http://www.youtube.com/embed/*id*" frameborder="0" allowfullscreen&gt;&lt;/iframe&gt;
  </code></pre>
  
  <p>The text is then parsed through <code>DOMdocument()</code> which converts the above into a self closing tag:</p>
  
  <pre><code>&lt;iframe class="EmbeddedVideo" title="YouTube video player" width="640" height="370" src="http://www.youtube.com/embed/xP4HhaUMB3I" frameborder="0" allowfullscreen=""/&gt;
  </code></pre>
  
  <p>Which breaks the page in Chrome &amp; Opera. If I manually change the html back to:</p>
  
  <pre><code>&lt;iframe class="EmbeddedVideo" title="YouTube video player" width="640" height="370" src="http://www.youtube.com/embed/xP4HhaUMB3I" frameborder="0" allowfullscreen=""&gt;&lt;/iframe&gt;
  </code></pre>
  
  <p>it works.</p>
  
  <p>Firstly, is there anything wrong with the self closing tag (because I can't see anything)?</p>
  
  <p>Is there a way to force domdocument() to use a 'proper' closing tag?</p>