Added system notification for update_engine.

chrome/browser/chromeos/update_observer.h

Index: chrome/browser/chromeos/update_observer.h
diff --git a/chrome/browser/chromeos/update_observer.h b/chrome/browser/chromeos/update_observer.h
new file mode 100644
index 0000000000000000000000000000000000000000..e19995804fdb13b1df32fac79ef1b8f395225f7f
--- /dev/null
+++ b/chrome/browser/chromeos/update_observer.h
@@ -0,0 +1,37 @@
+// Copyright (c) 2010 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_CHROMEOS_UPDATE_OBSERVER_H_
+#define CHROME_BROWSER_CHROMEOS_UPDATE_OBSERVER_H_
+
+#include "base/basictypes.h"
+#include "base/time.h"
+#include "chrome/browser/chromeos/cros/update_library.h"
+#include "chrome/browser/chromeos/notifications/system_notification.h"
+
+class Profile;
+
+namespace chromeos {
+
+// The update observer displays a system notification when the an update is
+// available.
+
+class UpdateObserver : public UpdateLibrary::Observer {
+ public:
+  explicit UpdateObserver(Profile* profile);
+  virtual ~UpdateObserver();
+
+ private:
+  virtual void Changed(UpdateLibrary* object);
+
+  SystemNotification notification_;
+  int progress_;  // Last displayed remaining time in minutes
+
+  DISALLOW_COPY_AND_ASSIGN(UpdateObserver);
+};
+
+}  // namespace chromeos
+
+#endif  // CHROME_BROWSER_CHROMEOS_UPDATE_OBSERVER_H_
+