adding correct assignement and copy constructors

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/branches/WX_2_8_BRANCH@46150 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

include/wx/mac/carbon/dataform.h

@@ -19,6 +19,7 @@ public:
 
     wxDataFormat();
     wxDataFormat(wxDataFormatId vType);
+    wxDataFormat(const wxDataFormat& rFormat);
     wxDataFormat(const wxString& rId);
     wxDataFormat(const wxChar* pId);
     wxDataFormat(NativeFormat vFormat);
@@ -36,6 +37,8 @@ public:
     bool operator!=(wxDataFormatId format) const
         { return m_type != (wxDataFormatId)format; }
 
+    wxDataFormat& operator=(const wxDataFormat& format);
+
     // explicit and implicit conversions to NativeFormat which is one of
     // standard data types (implicit conversion is useful for preserving the
     // compatibility with old code)