unset the button as temporary default item when it's destroyed (closes bug 1354875)

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@40135 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

include/wx/window.h

@@ -528,6 +528,9 @@ public:
         // set this child as temporary default
     virtual void SetTmpDefaultItem(wxWindow * WXUNUSED(win)) { }
 
+        // return the temporary default item, can be NULL
+    virtual wxWindow *GetTmpDefaultItem() const { return NULL; }
+
         // navigates in the specified direction by sending a wxNavigationKeyEvent
     virtual bool Navigate(int flags = wxNavigationKeyEvent::IsForward);