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

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@38920 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

src/os2/treectrl.cpp

@@ -26,17 +26,18 @@
 
 #if wxUSE_TREECTRL
 
+#include "wx/treectrl.h"
+
 #ifndef WX_PRECOMP
     #include "wx/dynarray.h"
+    #include "wx/log.h"
 #endif
 
 #include "wx/os2/private.h"
 
 #include "wx/app.h"
-#include "wx/log.h"
 #include "wx/imaglist.h"
 #include "wx/settings.h"
-#include "wx/os2/treectrl.h"
 
 // a macro to hide the ugliness of nested casts
 #define HITEM(item)     (HTREEITEM)(WXHTREEITEM)(item)