void DockConfigDlg::OnTreeDrag()
{
	if (tree.GetCursor() >= 0 && tree.GetParent(tree.GetCursor()) == 0)
		return;
	tree.DoDragAndDrop(InternalClip(tree, "dockwindowdrag"),
	                       tree.GetDragSample(), DND_MOVE) == DND_MOVE;
}