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

include/wx/gtk/colour.h

@@ -25,7 +25,7 @@ public:
     DEFINE_STD_WXCOLOUR_CONSTRUCTORS
     wxColour(const GdkColor& gdkColor);
 
-    ~wxColour();
+    virtual ~wxColour();
 
     bool Ok() const { return m_refData != NULL; }