mark all dtors which are virtual because base class dtor is virtual explicitly virtual themselves

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@41020 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

contrib/include/wx/applet/prepinclude.h

@@ -49,7 +49,7 @@ private:
     wxFileSystem *m_FS;
 public:
     wxIncludePrep() : wxHtmlProcessor() {}
-    ~wxIncludePrep() {}
+    virtual ~wxIncludePrep() {}
 	
 	// Process input text and return processed result
     wxString Process(const wxString& text) const;