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

ash/common/system/tray/system_tray_notifier.cc

 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "ash/common/system/tray/system_tray_notifier.h"
 
 #include "ash/common/system/accessibility_observer.h"
 #include "ash/common/system/date/clock_observer.h"
 #include "ash/common/system/ime/ime_observer.h"
 #include "ash/common/system/update/update_observer.h"
@@ skipping 83 matching lines @@
 }
 
 void SystemTrayNotifier::AddUpdateObserver(UpdateObserver* observer) {
   update_observers_.AddObserver(observer);
 }
 
 void SystemTrayNotifier::RemoveUpdateObserver(UpdateObserver* observer) {
   update_observers_.RemoveObserver(observer);
 }
 
-void SystemTrayNotifier::NotifyUpdateRecommended(const UpdateInfo& info) {
+void SystemTrayNotifier::ShowUpdateIcon(mojom::UpdateSeverity severity,
+                                        bool factory_reset_required) {
   for (auto& observer : update_observers_)
-    observer.OnUpdateRecommended(info);
+    observer.ShowUpdateIcon(severity, factory_reset_required);
 }
 
 void SystemTrayNotifier::AddUserObserver(UserObserver* observer) {
   user_observers_.AddObserver(observer);
 }
 
 void SystemTrayNotifier::RemoveUserObserver(UserObserver* observer) {
   user_observers_.RemoveObserver(observer);
 }
 
@@ skipping 212 matching lines @@
 
 void SystemTrayNotifier::NotifyVirtualKeyboardSuppressionChanged(
     bool suppressed) {
   for (auto& observer : virtual_keyboard_observers_)
     observer.OnKeyboardSuppressionChanged(suppressed);
 }
 
 #endif  // defined(OS_CHROMEOS)
 
 }  // namespace ash