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/x11/bitmap.h

@@ -37,7 +37,7 @@ public:
     wxMask( const wxBitmap& bitmap, const wxColour& colour );
     wxMask( const wxBitmap& bitmap, int paletteIndex );
     wxMask( const wxBitmap& bitmap );
-    ~wxMask();
+    virtual ~wxMask();
 
     bool Create( const wxBitmap& bitmap, const wxColour& colour );
     bool Create( const wxBitmap& bitmap, int paletteIndex );