add PostSizeEvent() and use it in wxMSW status bar code (#9795)

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@54837 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

include/wx/msw/frame.h

@@ -92,7 +92,7 @@ public:
 #endif // tooltips
 
     // override the base class function to handle iconized/maximized frames
-    virtual void SendSizeEvent();
+    virtual void SendSizeEvent(int flags = 0);
 
     virtual wxPoint GetClientAreaOrigin() const;