ReorderListBox doesn't support hybrid Winform applications

[jonashogstrom]

If a ReorderListBox will throw a NullReferenceException when used in a winform hybrid application. the reason is that the DragPreviewAdorner uses Application.Current, but this static property is not assigned when running in a winform application. A solution is to change the following method:

    private static void GetCurrentDPI(out double x, out double y)
    {
        Matrix m = PresentationSource.FromVisual(Application.Current.MainWindow).CompositionTarget.TransformToDevice;
        x = 96 / m.M11;
        y = 96 / m.M22;
    }

to

    private static void GetCurrentDPI(out double x, out double y, FrameworkElement element)
    {
        Matrix m = PresentationSource.FromVisual(element).CompositionTarget.TransformToDevice;
        x = 96 / m.M11;
        y = 96 / m.M22;
    }

and pass the current element in SetPreviewElement:

    public void SetPreviewElement(FrameworkElement element)
    {
        //...
        GetCurrentDPI(out x, out y, element);

Side note: the class NotifyWorker seems to have the same issue in the OnClientException method... haven't looked at how that could be handled. We aren't using that class.