corrections for wxGtk compilation under Darwin/Mac OS X

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@11132 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

include/wx/gtk1/popupwin.h

@@ -27,7 +27,10 @@ class wxPopupWindow: public wxPopupWindowBase
 {
 public:
     wxPopupWindow() { }
-
+#ifdef __DARWIN__
+    virtual ~wxPopupWindow() { }
+#endif
+    
     wxPopupWindow(wxWindow *parent) { (void)Create(parent); }
     bool Create(wxWindow *parent, int flags = wxBORDER_NONE);