Wires up immersive mode for chrome and mash

ash/mus/bridge/wm_shell_mus.h

Index: ash/mus/bridge/wm_shell_mus.h
diff --git a/ash/mus/bridge/wm_shell_mus.h b/ash/mus/bridge/wm_shell_mus.h
index 29b2d23e2599fb8ccea88f4bf012e0f0cb1c6960..191cf2a3d59c000e1b51a6f8f76e102b45333160 100644
--- a/ash/mus/bridge/wm_shell_mus.h
+++ b/ash/mus/bridge/wm_shell_mus.h
@@ -32,6 +32,7 @@ namespace mus {
 
 class AcceleratorControllerDelegateMus;
 class AcceleratorControllerRegistrar;
+class ImmersiveHandlerFactoryMus;
 class WindowManager;
 class WmRootWindowControllerMus;
 class WmShellMusTestApi;
@@ -135,6 +136,7 @@ class WmShellMus : public WmShell, public ui::WindowTreeClientObserver {
       accelerator_controller_delegate_;
   std::unique_ptr<AcceleratorControllerRegistrar>
       accelerator_controller_registrar_;
+  std::unique_ptr<ImmersiveHandlerFactoryMus> immersive_handler_factory_;
   std::unique_ptr<SessionStateDelegate> session_state_delegate_;
 
   base::ObserverList<WmActivationObserver> activation_observers_;