mus: Forward user activity from window server to detector.

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 4b13ba484446ef767ee057e6ed27cd4a679b3680..1be85ff79853e4dd3359b54555a62b8cc181c0e2 100644
--- a/ash/mus/bridge/wm_shell_mus.h
+++ b/ash/mus/bridge/wm_shell_mus.h
@@ -19,6 +19,11 @@ namespace aura {
 class WindowTreeClient;
 }
 
+namespace ui {
+class UserActivityDetector;
+class UserActivityPowerManagerNotifier;
+}
+
 namespace views {
 class PointerWatcherEventRouter;
 }
@@ -30,6 +35,7 @@ class AcceleratorControllerDelegateMus;
 class AcceleratorControllerRegistrar;
 class ImmersiveHandlerFactoryMus;
 class RootWindowController;
+class UserActivityForwarder;
 class WindowManager;
 class WmShellMusTestApi;
 
@@ -136,6 +142,10 @@ class WmShellMus : public WmShell,
 
   base::ObserverList<WmActivationObserver> activation_observers_;
 
+  std::unique_ptr<ui::UserActivityDetector> user_activity_detector_;
+  std::unique_ptr<ui::UserActivityPowerManagerNotifier> user_activity_notifier_;
+  std::unique_ptr<UserActivityForwarder> user_activity_forwarder_;
+
   DISALLOW_COPY_AND_ASSIGN(WmShellMus);
 };