removing event handlers on non-owned windows when the destroy event is sent

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@62985 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

include/wx/osx/nonownedwnd.h

@@ -116,6 +116,8 @@ protected:
     virtual bool OSXShowWithEffect(bool show,
                                    wxShowEffect effect,
                                    unsigned timeout);
+    
+    void OnWindowDestroy( wxWindowDestroyEvent &event);
 
     wxNonOwnedWindowImpl* m_nowpeer ;