Bug 214271 [CommonNavigator] Undo/redo not enabled if nothing selected
bundles/org.eclipse.ui.navigator.resources/src/org/eclipse/ui/internal/navigator/resources/actions/RefactorActionProvider.java
private UndoRedoActionGroup undoRedoGroup;
	private RefactorActionGroup refactorGroup;
	private ICommonActionExtensionSite site;
	/*
	 * (non-Javadoc)
	 * 
	 * @see org.eclipse.ui.navigator.CommonActionProvider#init(org.eclipse.ui.navigator.ICommonActionExtensionSite)
	 */