Restores the panel to its previous docking position.
The Restore method allows a panel which is hidden, auto hidden or floated to be restored to its previous docking position.
An end-user can restore a floating panel's position by double-clicking its caption. When a DocumentManager is placed to the form where the DockManager resides, double-clicking a floating panel's caption maximizes the panel to take up the entire desktop.
Although the Restore method affects a panel's DockPanel.Visibility, it does not fire the VisibilityChanged event.