why was this class made a wxControlContainer (rev. 1.7), this doesn't seem to make sense -- and if it does it should probably be done at the base class level, not here

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@45054 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

include/wx/treebook.h

@@ -18,7 +18,6 @@
 
 #include "wx/bookctrl.h"
 #include "wx/treectrl.h"        // for wxArrayTreeItemIds
-#include "wx/containr.h"
 
 typedef wxWindow wxTreebookPage;
 
@@ -227,7 +226,6 @@ private:
 
     DECLARE_EVENT_TABLE()
     DECLARE_DYNAMIC_CLASS_NO_COPY(wxTreebook)
-    WX_DECLARE_CONTROL_CONTAINER();
 };