title: Storyboard.begin() throws an InvalidOperationException
body: <p>I am not sure what is going on here. I am following the example provided by Microsoft. Everything is done on the back end because I need to decide if you user should enter stuff into a text field or should the text field value be displayed as normal text. The code is as follows:</p>
  
  <pre><code>            nameInput.Name = "inputName";
              nameInput.Text = "Journey Name";
              nameInput.KeyUp += onNameInput;
  
              ColorAnimation animation = new ColorAnimation();
              animation.From = Colors.Blue;
              animation.To = Colors.White;
              animation.Duration = new Duration(TimeSpan.FromMilliseconds(100));
              animation.RepeatBehavior = RepeatBehavior.Forever;
              Storyboard.SetTarget(animation, nameInput);
              Storyboard.SetTargetProperty(animation, new PropertyPath(TextBlock.ForegroundProperty));
              storyBoard.Children.Add(animation);
              journeyStackPanel.Children.Add(nameInput);
              ClockState state = storyBoard.GetCurrentState();
              storyBoard.Begin(); //&lt;---Crashes here
  </code></pre>
  
  <p>I am following the</p>
  
  <pre><code>http://msdn.microsoft.com/en-us/library/cc672995(v=vs.95).aspx
  </code></pre>
  
  <p>example. I am not sure what is going on, unfortunately the debugger does not spit out any more information. Maybe I am missing a step? I am sorry that I am being a little vague but this is all the information I have on the issue.</p>
  
  <p>Any help is greatly appreciated!!</p>