wxDFB: fix rendering artefacts when scrolling wxScrolledWindow that contains other widgets

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@44290 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

include/wx/menu.h

@@ -488,6 +488,8 @@ public:
     // update all menu item states in all menus
     virtual void UpdateMenus();
 
+    virtual bool CanBeOutsideClientArea() const { return true; }
+
 protected:
     // the list of all our menus
     wxMenuList m_menus;