protected override void Arrange()
        {
            base.Arrange();

            coordinator = new TestPasswordChangeCoordinator();
            maskedPasswordControl = new MaskedPasswordTextBox(coordinator);
        }
        private static void UnsecuredPasswordChangedCallback(DependencyObject d, DependencyPropertyChangedEventArgs e)
        {
            MaskedPasswordTextBox maskedBox = d as MaskedPasswordTextBox;

            if (maskedBox != null)
            {
                maskedBox.coordinator.Value = (string)e.NewValue;
            }
        }