title: kotlin synthetic Integer cannot be cast to floating button
body: <p>Why does</p>
  
  <p><code>val fabOpen = view.findViewById(R.id.fab_open) as FloatingActionButton</code></p>
  
  <p>work correctly and not error out but the kotlin synthetic of</p>
  
  <p><code>val fabOpen = R.id.fab_open as FloatingActionButton</code></p>
  
  <p>gives me the</p>
  
  <p><code>java.lang.Integer cannot be cast to android.support.design.widget.FloatingActionButton</code></p>
  
  <p>error?  They both show that they are casting as <code>FloatingActionButton</code>.  Using the synthetics is not only less code, it's better memory management and I'd prefer to do it this way.  Is there something I am missing?</p>
  
  <p>****Update****  I forgot to mention I am trying access the <code>FloatingActionButton</code> inside of a fragment if that makes a difference.</p>