Add wxMenuBar::OSXGetAppleMenu().

Native OS X apps sometimes have certain app-wide comments in the
Apple/app menu ("Check for Updates" is a typical example).  Make it
possible to write well-behaved OS X apps by exposing this menu to user
code.

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@75231 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

include/wx/osx/menu.h

@@ -146,6 +146,10 @@ public:
     // call this function to update it (m_menuBarFrame should be !NULL)
     void Refresh(bool eraseBackground = true, const wxRect *rect = NULL);
 
+#if wxABI_VERSION >= 30001
+    wxMenu *OSXGetAppleMenu() const { return m_appleMenu; }
+#endif
+
     static void SetAutoWindowMenu( bool enable ) { s_macAutoWindowMenu = enable ; }
     static bool GetAutoWindowMenu() { return s_macAutoWindowMenu ; }