Include wx/sizer.h and wx/layout.h according to precompiled headers of wx/wx.h (with other minor cleaning).

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@39627 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

src/gtk/dataview.cpp

@@ -19,12 +19,12 @@
 #ifndef WX_PRECOMP
     #include "wx/log.h"
     #include "wx/dcclient.h"
+    #include "wx/sizer.h"
 #endif
 
 #include "wx/stockitem.h"
 #include "wx/calctrl.h"
 #include "wx/popupwin.h"
-#include "wx/sizer.h"
 
 #include "wx/gtk/private.h"
 #include "wx/gtk/win_gtk.h"