Insert missing include file

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@57901 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

src/gtk/textctrl.cpp

@@ -15,6 +15,7 @@
 #include "wx/textctrl.h"
 
 #ifndef WX_PRECOMP
+    #include "wx/app.h"
     #include "wx/intl.h"
     #include "wx/log.h"
     #include "wx/utils.h"