qt_mac_set_dock_menu missing from Qt (though mentioned in docs)

My app uses a menu attached to the Mac dock icon for much of its functionality (on other platforms, it uses a system-tray icon). On Qt4 there is an exported function, qt_mac_set_dock_menu, which allows a QMenu to be attached to the dock icon. This function is mentioned in the documentation for the Qt 5 beta (exportedfunctions.html) but is missing from the library. When I link my app, I get an "unresolved symbol" error.

The dock menu is a pretty important feature on Macs and widely used; it would make Qt less viable if this function were to be excluded.