fix the bug which prevented the same wxFile/DirDialog object from being used twice (patch 1485127)

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@39397 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

include/wx/gtk/dirdlg.h

@@ -29,7 +29,7 @@ public:
                 const wxSize& size = wxDefaultSize,
                 const wxString& name = wxDirDialogNameStr);
 
-    virtual ~wxDirDialogGTK();
+    virtual ~wxDirDialogGTK() {}
 
 
 public:     // overrides from wxGenericDirDialog
@@ -41,9 +41,6 @@ public:     // overrides from wxGenericDirDialog
     virtual bool Show( bool show = true );
 
 
-//private:      must be accessible by GTK callback
-    bool m_destroyed_by_delete;
-
 protected:
     // override this from wxTLW since the native
     // form doesn't have any m_wxwindow