Always write end record unless one has already been written.

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@51008 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

include/wx/zipstrm.h

@@ -346,6 +346,7 @@ private:
     int m_level;
     wxFileOffset m_offsetAdjustment;
     wxString m_Comment;
+    bool m_endrecWritten;
 
     DECLARE_NO_COPY_CLASS(wxZipOutputStream)
 };