title: Add multiple classes with ng-class, where one of the classes is conditional
body: <p>I got this code: </p>
  
  <pre><code>ng-class="{selectedHeader: key == selectedCol}"
  </code></pre>
  
  <p>It works but I would like too add the 'key' value as a class too, Ive tried:</p>
  
  <pre><code>ng-class="[{selectedHeader: key == selectedCol}, key]"
  </code></pre>
  
  <p>But that wont work, does anyone know how to solve this?</p>