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

chrome/browser/lifetime/application_lifetime.h

Index: chrome/browser/lifetime/application_lifetime.h
diff --git a/chrome/browser/lifetime/application_lifetime.h b/chrome/browser/lifetime/application_lifetime.h
index 2d426ae8a94698cd3acf939ab2f1a6f93be81b18..8ed09235e134137f9de8464409e469e54f06aeff 100644
--- a/chrome/browser/lifetime/application_lifetime.h
+++ b/chrome/browser/lifetime/application_lifetime.h
@@ -76,7 +76,10 @@ void NotifyAppTerminating();
 
 // Send out notifications.
 // For ChromeOS, also request session manager to end the session.
-void NotifyAndTerminate(bool fast_path);
+// |always_reboot| is used on ChromeOS to signal that a reboot is required, even
+// if a system update is not available. This is useful if, for example, a
+// component flash update was applied.

[Nico, 2016/12/02 01:20:07]

Consider using enums instead of bools. Writing

  enum RebootStyle { kForceReboot, kNoReboot };
  void NotifyAndTerminate(bool fast_path, bool always_reboot = kNoReboot);

is not any more work, but at the calling side

  foo->NotifyAndTerminal(foo, ApplicationLifetime::kForceReboot);

is way more readable. (Also, style guide discourages default args iirc)

[Greg K, 2016/12/03 00:05:42]

I agree about the enumeration. That being said, I read the style guide and it
does encourage using a default argument or function overload for a case like
this were only one caller cares about that value.

That being said, it says when in doubt, prefer function overloads so that's how
I will do this.

+void NotifyAndTerminate(bool fast_path, bool always_reboot = false);
 
 #if !defined(OS_ANDROID)
 // Called once the application is exiting.