Get rid of ugly wxCONTROL_ITEMCONTAINER_CLIENTDATAOBJECT_RECAST macro.

Replace it with wxWindowWithItems<> template class which takes care of
disambiguating between the two inherited Get/SetClientXXX() versions and use
it as a base class in all clases that previously used the macro.

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@68460 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

include/wx/univ/combobox.h

@@ -34,7 +34,8 @@ class WXDLLIMPEXP_FWD_CORE wxListBox;
 // NB: Normally we'd like wxComboBox to inherit from wxComboBoxBase, but here
 //     we can't really do that since both wxComboBoxBase and wxComboCtrl inherit
 //     from wxTextCtrl.
-class WXDLLIMPEXP_CORE wxComboBox : public wxComboCtrl, public wxItemContainer
+class WXDLLIMPEXP_CORE wxComboBox :
+    public wxWindowWithItems<wxComboCtrl, wxItemContainer>
 {
 public:
     // ctors and such
@@ -141,8 +142,6 @@ public:
     virtual int GetSelection() const;
     virtual wxString GetStringSelection() const;
 
-    wxCONTROL_ITEMCONTAINER_CLIENTDATAOBJECT_RECAST
-
     // we have our own input handler and our own actions
     // (but wxComboCtrl already handled Popup/Dismiss)
     /*