ash: Use system tray mojo interface to show system update tray icon

ash/common/system/tray/system_tray_notifier.h

Index: ash/common/system/tray/system_tray_notifier.h
diff --git a/ash/common/system/tray/system_tray_notifier.h b/ash/common/system/tray/system_tray_notifier.h
index 7b1ccb6af6c3e2e153f77c159784f34e8f0b8fdf..6c37e3980b93b1ae3e5db9116cf41c3bb6885801 100644
--- a/ash/common/system/tray/system_tray_notifier.h
+++ b/ash/common/system/tray/system_tray_notifier.h
@@ -22,7 +22,6 @@ namespace ash {
 class AccessibilityObserver;
 class ClockObserver;
 class IMEObserver;
-struct UpdateInfo;
 class UpdateObserver;
 class UserObserver;
 
@@ -41,6 +40,10 @@ class TracingObserver;
 class VirtualKeyboardObserver;
 #endif
 
+namespace mojom {
+enum class UpdateSeverity;
+}
+
 // Observer and notification manager for the ash system tray.
 class ASH_EXPORT SystemTrayNotifier {
  public:
@@ -70,7 +73,8 @@ class ASH_EXPORT SystemTrayNotifier {
   // OS updates.
   void AddUpdateObserver(UpdateObserver* observer);
   void RemoveUpdateObserver(UpdateObserver* observer);
-  void NotifyUpdateRecommended(const UpdateInfo& info);
+  void ShowUpdateIcon(mojom::UpdateSeverity severity,
+                      bool factory_reset_required);
 
   // User.
   void AddUserObserver(UserObserver* observer);