i think they got rid of it for immersive mode everywhere when expanded desktop is enabled. basically enable expanded desktop, then slide your finger in from the bottom of the screen, and for a few seconds youll see a semi transparent nav bar which will auto hide.
XDA Developers was founded by developers, for developers. It is now a valuable resource for people who want to make the most of their mobile devices, from customizing the look and feel to adding new functionality. Are you a developer?