Made return a const reference

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@2208 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

include/wx/msw/app.h

@@ -78,7 +78,7 @@ class WXDLLEXPORT wxApp: public wxEvtHandler
   inline void SetExitOnFrameDelete(bool flag) { m_exitOnFrameDelete = flag; }
   inline bool GetExitOnFrameDelete() const { return m_exitOnFrameDelete; }
 
-  inline wxString GetAppName() const {
+  inline const wxString& GetAppName() const {
       if (m_appName != "")
         return m_appName;
       else return m_className;