title: Angular2 showing null in IE
body: <p>I have the following in an Angular2 component:</p>
  
  <p><code>&lt;div ng-if="heading" [innerHTML]="heading"&gt;&lt;/div&gt;</code></p>
  
  <p>Chrome &amp; Safari work fine - but IE is showing <code>null</code> in the DIV. I have no idea why... heading is <code>undefined</code>, double-checked!</p>