Move wxInfoBar to core library from adv.

This is necessary in order to be able to use it in the print preview (an
upcoming change).

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@64213 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

include/wx/gtk/infobar.h

@@ -20,7 +20,7 @@
 // notice that the native GTK+ implementation is only available since
 // (relatively recent) 2.18 so we inherit from the generic one to be able to
 // fall back to it if GTK+ version is determined to be too old during run-time
-class WXDLLIMPEXP_ADV wxInfoBar : public wxInfoBarGeneric
+class WXDLLIMPEXP_CORE wxInfoBar : public wxInfoBarGeneric
 {
 public:
     wxInfoBar() { Init(); }