Add update available icon in system tray

chrome/browser/upgrade_detector.h

 // Copyright (c) 2011 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.
 
 #ifndef CHROME_BROWSER_UPGRADE_DETECTOR_H_
 #define CHROME_BROWSER_UPGRADE_DETECTOR_H_
 
 #include "base/gtest_prod_util.h"
 #include "base/macros.h"
+#include "base/observer_list.h"
 #include "base/timer/timer.h"
 #include "chrome/browser/chrome_notification_types.h"
 #include "ui/base/idle/idle.h"
 #include "ui/gfx/image/image.h"
 
 class PrefRegistrySimple;
 
 ///////////////////////////////////////////////////////////////////////////////
 // UpgradeDetector
 //
 // This class is a singleton class that monitors when an upgrade happens in the
 // background. We basically ask Omaha what it thinks the latest version is and
 // if our version is lower we send out a notification upon:
 //   a) Detecting an upgrade and...
 //   b) When we think the user should be notified about the upgrade.
 // The latter happens much later, since we don't want to be too annoying.
 //
 class UpgradeDetector {
  public:
+  class UpgradeObserver {

[sky, 2017/05/18 23:41:56]

Remove this to it's own file (see chromium style guide).

[weidongg, 2017/05/19 01:29:53]

Done.

+   public:
+    virtual ~UpgradeObserver();

[sky, 2017/05/18 23:41:56]

Move to protected section, also you can inline this (style guide allows it).

[weidongg, 2017/05/19 01:29:53]

Done.

+
+    // Triggered when a software update is available, but downloading requires
+    // user's agreement as current connection is cellular.
+    virtual void OnUpdateOverCellularAvailable() = 0;
+  };
+
   // The Homeland Security Upgrade Advisory System.
   enum UpgradeNotificationAnnoyanceLevel {
     UPGRADE_ANNOYANCE_NONE = 0,  // What? Me worry?
     UPGRADE_ANNOYANCE_LOW,       // Green.
     UPGRADE_ANNOYANCE_ELEVATED,  // Yellow.
     UPGRADE_ANNOYANCE_HIGH,      // Red.
     UPGRADE_ANNOYANCE_SEVERE,    // Orange.
     UPGRADE_ANNOYANCE_CRITICAL,  // Red exclamation mark.
   };
 
@@ skipping 33 matching lines @@
 
   // Retrieves the right icon based on the degree of severity (see
   // UpgradeNotificationAnnoyanceLevel, each level has an an accompanying icon
   // to go with it) to display within the app menu.
   gfx::Image GetIcon();
 
   UpgradeNotificationAnnoyanceLevel upgrade_notification_stage() const {
     return upgrade_notification_stage_;
   }
 
+  void AddObserver(UpgradeObserver* observer);
+
+  void RemoveObserver(UpgradeObserver* observer);
+
  protected:
   enum UpgradeAvailable {
     // If no update is available and current install is recent enough.
     UPGRADE_AVAILABLE_NONE,
     // If a regular update is available.
     UPGRADE_AVAILABLE_REGULAR,
     // If a critical update to Chrome has been installed, such as a zero-day
     // fix.
     UPGRADE_AVAILABLE_CRITICAL,
     // If no update to Chrome has been installed for more than the recommended
     // time.
     UPGRADE_NEEDED_OUTDATED_INSTALL,
     // If no update to Chrome has been installed for more than the recommended
     // time AND auto-update is turned off.
     UPGRADE_NEEDED_OUTDATED_INSTALL_NO_AU,
   };
 
   UpgradeDetector();
 
   // Sends out UPGRADE_RECOMMENDED notification and set notify_upgrade_.
   void NotifyUpgradeRecommended();
 
+  // The function that sends out a notification that lets the rest of the UI
+  // know we should notify the user that a new update is available to download
+  // over cellular connection.
+  void NotifyUpdateOverCellularAvailable();
+
   // Triggers a critical update, which starts a timer that checks the machine
   // idle state. Protected and virtual so that it could be overridden by tests.
   virtual void TriggerCriticalUpdate();
 
   UpgradeAvailable upgrade_available() const { return upgrade_available_; }
   void set_upgrade_available(UpgradeAvailable available) {
     upgrade_available_ = available;
   }
 
   void set_best_effort_experiment_updates_available(bool available) {
@@ skipping 54 matching lines @@
   // UPGRADE_AVAILABLE_CRITICAL.
   base::RepeatingTimer idle_check_timer_;
 
   // The stage at which the annoyance level for upgrade notifications is at.
   UpgradeNotificationAnnoyanceLevel upgrade_notification_stage_;
 
   // Whether we have waited long enough after detecting an upgrade (to see
   // is we should start nagging about upgrading).
   bool notify_upgrade_;
 
+  base::ObserverList<UpgradeObserver> observer_list_;
+
   DISALLOW_COPY_AND_ASSIGN(UpgradeDetector);
 };
 
 #endif  // CHROME_BROWSER_UPGRADE_DETECTOR_H_