/// <summary>
/// Holds up the test execution for the given duration without blocking the UI thread.
/// </summary>
void UIPause(int sec)
{
    Storyboard PauseSB = new Storyboard() { Duration = new Duration(new TimeSpan(0, 0, sec)) };
    PauseSB.Completed += (sender, e) => { TestComplete(); };
    PauseSB.Begin();
}