Refactor: extract menu event handling logic from wxMenu::SendEvent().

Make this logic available for reuse with the events of different kind, e.g.
wxMenuEvent in the upcoming commit.

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@78228 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

include/wx/menu.h

@@ -388,6 +388,12 @@ protected:
 
     static bool      ms_locked;
 
+
+private:
+    // Helper of SendEvent(): sends the event to its intended recipients,
+    // returns true if it was processed.
+    static bool DoProcessEvent(wxMenuBase* menu, wxEvent& event, wxWindow* win);
+
     wxDECLARE_NO_COPY_CLASS(wxMenuBase);
 };