remove WXWIN_COMPATIBILITY_2_6, add WXWIN_COMPATIBILITY_3_0

closes #15792

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@75532 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

include/wx/html/winpars.h

@@ -66,10 +66,6 @@ public:
 
     // returns interface to the rendering window
     wxHtmlWindowInterface *GetWindowInterface() {return m_windowInterface;}
-#if WXWIN_COMPATIBILITY_2_6
-    // deprecated, use GetWindowInterface()->GetHTMLWindow() instead
-    wxDEPRECATED( wxHtmlWindow *GetWindow() );
-#endif
 
     // Sets fonts to be used when displaying HTML page. (if size null then default sizes used).
     void SetFonts(const wxString& normal_face, const wxString& fixed_face, const int *sizes = NULL);