Add update available icon in system tray

chrome/browser/upgrade_detector.cc

 // Copyright (c) 2012 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 "chrome/browser/upgrade_detector.h"
 
 #include "base/bind.h"
 #include "base/command_line.h"
 #include "chrome/app/vector_icons/vector_icons.h"
 #include "chrome/browser/chrome_notification_types.h"
@@ skipping 69 matching lines @@
   if (upgrade_available_ == UPGRADE_NEEDED_OUTDATED_INSTALL) {
     TriggerNotification(chrome::NOTIFICATION_OUTDATED_INSTALL);
   } else if (upgrade_available_ == UPGRADE_NEEDED_OUTDATED_INSTALL_NO_AU) {
     TriggerNotification(chrome::NOTIFICATION_OUTDATED_INSTALL_NO_AU);
   } else if (upgrade_available_ == UPGRADE_AVAILABLE_CRITICAL ||
              critical_experiment_updates_available_) {
     TriggerCriticalUpdate();
   }
 }
 
+void UpgradeDetector::NotifyUpdateOverCellularAvailable() {
+  for (auto& observer : observer_list_)
+    observer.OnUpdateOverCellularAvailable();
+}
+
 void UpgradeDetector::TriggerCriticalUpdate() {
   const base::TimeDelta idle_timer = UseTestingIntervals() ?
       base::TimeDelta::FromSeconds(kIdleRepeatingTimerWait) :
       base::TimeDelta::FromMinutes(kIdleRepeatingTimerWait);
   idle_check_timer_.Start(FROM_HERE, idle_timer, this,
                           &UpgradeDetector::CheckIdle);
 }
 
 void UpgradeDetector::CheckIdle() {
   // CalculateIdleState expects an interval in seconds.
@@ skipping 31 matching lines @@
       break;
     case ui::IDLE_STATE_ACTIVE:
     case ui::IDLE_STATE_UNKNOWN:
       break;
     default:
       NOTREACHED();  // Need to add any new value above (either providing
                      // automatic restart or show notification to user).
       break;
   }
 }
+
+void UpgradeDetector::AddObserver(UpgradeObserver* observer) {
+  observer_list_.AddObserver(observer);
+}
+
+void UpgradeDetector::RemoveObserver(UpgradeObserver* observer) {
+  observer_list_.RemoveObserver(observer);
+}