Display "Restart to update" dialog to Chrome OS users.

chrome/browser/lifetime/application_lifetime.h

 // 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.
 
 #ifndef CHROME_BROWSER_LIFETIME_APPLICATION_LIFETIME_H_
 #define CHROME_BROWSER_LIFETIME_APPLICATION_LIFETIME_H_
 
 #include "base/compiler_specific.h"
 #include "build/build_config.h"
 
@@ skipping 58 matching lines @@
 void SessionEnding();
 
 #endif  // !defined(OS_ANDROID)
 
 // Emits APP_TERMINATING notification. It is guaranteed that the
 // notification is sent only once.
 void NotifyAppTerminating();
 
 // Send out notifications.
 // For ChromeOS, also request session manager to end the session.
+// |lifetime| is used to signal whether or not a reboot should be forced. By
+// default, the functions only reboot the system if an update is available. When
+// a component flash update is present, but not a system update, the
+// kForceReboot flag is passed.
+enum class ApplicationLifetime { kForceReboot, kOptionalReboot };

[James Cook, 2016/12/03 00:18:20]

nit: I wouldn't call the class itself ApplicationLifetime. It's more like a
RebootPolicy or something. Nico might have been thinking this code was in a
class ApplicationLifetime based on the filename.

[Nico, 2016/12/03 00:23:13]

Yes, I thought this was in a class and used a plain non-class enum. Using an
enum class is fine if you prefer though; James's suggestion sounds good to me.

[Greg K, 2016/12/06 00:13:15]

Done.

 void NotifyAndTerminate(bool fast_path);
+void NotifyAndTerminate(bool fast_path, ApplicationLifetime lifetime);
 
 #if !defined(OS_ANDROID)
 // Called once the application is exiting.
 void OnAppExiting();
 
 // Called once the application is exiting to do any platform specific
 // processing required.
 void HandleAppExitingForPlatform();
 #endif  // !defined(OS_ANDROID)
 
 }  // namespace chrome
 
 #endif  // CHROME_BROWSER_LIFETIME_APPLICATION_LIFETIME_H_