Added stub for the new pure virtual DoInsert method

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@20979 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

include/wx/cocoa/choice.h

@@ -63,6 +63,7 @@ public:
     virtual int FindString(const wxString&) const;
     virtual int GetSelection() const;
     virtual int DoAppend(const wxString&);
+    virtual int DoInsert(const wxString&, int);
     virtual void DoSetItemClientData(int, void*);
     virtual void* DoGetItemClientData(int) const;
     virtual void DoSetItemClientObject(int, wxClientData*);

src/cocoa/choice.mm

@@ -76,6 +76,11 @@ int wxChoice::DoAppend(const wxString&)
     return 0;
 }
 
+int wxChoice::DoInsert(const wxString&, int)
+{
+    return 0;
+}
+
 void wxChoice::DoSetItemClientData(int, void*)
 {
 }