fixed bug in wxFrame::OnActivate

(added virtual void RemoveChild() which make sure OnActivate
won't accidentally use invalid m_winLastFocused ptr)


git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@10298 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

src/msw/frame.cpp

@@ -799,6 +799,13 @@ void wxFrame::OnActivate(wxActivateEvent& event)
     }
 }
 
+void wxFrame::RemoveChild( wxWindowBase *child )
+{
+    if ( child == m_winLastFocused )
+        m_winLastFocused = NULL;
+    wxFrameBase::RemoveChild(child);
+}
+
 // ----------------------------------------------------------------------------
 // tool/status bar stuff
 // ----------------------------------------------------------------------------