title: ControlBrushKey throws exception in PresentationFramework.dll
body: <p>The Unhandled exception is thrown only when I have that ControlBrushKey line, and it does not break pointing to that location.</p>
  
  <pre><code>var x2 = new Style();
  x2.Resources.Add(SystemColors.ControlBrushKey, Colors.Red);
  myListbox.ItemContainerStyle = x2
  </code></pre>
  
  <p>An unhandled exception of type 'System.InvalidCastException' occurred in PresentationFramework.dll</p>
  
  <p>Additional information: Unable to cast object of type 'System.Windows.Media.Color' to type 'System.Windows.Media.Brush'.</p>
  
  <p>Is this PresentationFramework.dll bug or am I missing something? I use .NET4</p>
  
  <p>(PS: I have to do it on code)</p>