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

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@39505 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

src/generic/treectlg.cpp

@@ -32,6 +32,7 @@
     #include "wx/dcclient.h"
     #include "wx/timer.h"
     #include "wx/settings.h"
+    #include "wx/listbox.h"
 #endif
 
 #include "wx/generic/treectlg.h"
@@ -3566,10 +3567,6 @@ void wxGenericTreeCtrl::OnGetToolTip( wxTreeEvent &event )
 // be removed, as well as the #else case below.
 #define _USE_VISATTR 0
 
-#if _USE_VISATTR
-#include "wx/listbox.h"
-#endif
-
 //static
 wxVisualAttributes
 #if _USE_VISATTR