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

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@39760 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

include/wx/wx.h

@@ -34,6 +34,7 @@
 #include "wx/panel.h"
 #include "wx/toplevel.h"
 #include "wx/frame.h"
+#include "wx/region.h"
 #include "wx/bitmap.h"
 #include "wx/colour.h"
 #include "wx/font.h"
@@ -93,4 +94,3 @@
 #endif // wxUSE_GUI
 
 #endif // _WX_WX_H_
-