Moves ash::user::LoginStatus to ash/common

ash/root_window_controller.h

Index: ash/root_window_controller.h
diff --git a/ash/root_window_controller.h b/ash/root_window_controller.h
index 926ca6a98e8282d0611f371eff9a0b95b66e7fb2..7d777472dea2506482fbbafaf109dc4a99be7c3b 100644
--- a/ash/root_window_controller.h
+++ b/ash/root_window_controller.h
@@ -194,7 +194,7 @@ class ASH_EXPORT RootWindowController : public ShellObserver {
 
   // Called when the login status changes after login (such as lock/unlock).
   // TODO(oshima): Investigate if we can merge this and |OnLoginStateChanged|.
-  void UpdateAfterLoginStatusChange(user::LoginStatus status);
+  void UpdateAfterLoginStatusChange(LoginStatus status);
 
   // Called when the brightness/grayscale animation from white to the login
   // desktop background image has started.  Starts |boot_splash_screen_|'s
@@ -270,7 +270,7 @@ class ASH_EXPORT RootWindowController : public ShellObserver {
   void OnMenuClosed();
 
   // Overridden from ShellObserver.
-  void OnLoginStateChanged(user::LoginStatus status) override;
+  void OnLoginStateChanged(LoginStatus status) override;
   void OnTouchHudProjectionToggled(bool enabled) override;
 
   std::unique_ptr<AshWindowTreeHost> ash_host_;