[whatwg] Empty content models

<img> explicitly says "The img element must be empty." in the prose. Same  
for <br>. This isn't done for the <base>, <link>, <meta>, <hr>, <embed>,  
<param>, <area>, <col> and <event-source>. (I suppose there might be  
others if I skipped one.)


-- 
Anne van Kesteren
<http://annevankesteren.nl/>
<http://www.opera.com/>