Fix for export warning when compiling a DLL.

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@19019 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

include/wx/msw/listctrl.h

@@ -370,6 +370,9 @@ protected:
     long              m_baseStyle;  // Basic Windows style flags, for recreation purposes
     int               m_colCount;   // Windows doesn't have GetColumnCount so must
                                     // keep track of inserted/deleted columns
+    long              m_count;      // Keep track of item count to save calls to
+                                    // ListView_GetItemCount
+    bool              m_ignoreChangeMessages;
 
     // TRUE if we have any internal data (user data & attributes)
     bool m_AnyInternalData;