chromeos: Migrate SignOut and RequestRestartForUpdate to mojo interface

chrome/browser/ui/ash/system_tray_client.cc

Index: chrome/browser/ui/ash/system_tray_client.cc
diff --git a/chrome/browser/ui/ash/system_tray_client.cc b/chrome/browser/ui/ash/system_tray_client.cc
index d848ee93b63ef81555f2f64f65e4e0d2dd36bd2e..c6b8ea7a7fc8d7f4df89f8b71cf32949a3b61348 100644
--- a/chrome/browser/ui/ash/system_tray_client.cc
+++ b/chrome/browser/ui/ash/system_tray_client.cc
@@ -20,6 +20,7 @@
 #include "chrome/browser/chromeos/set_time_dialog.h"
 #include "chrome/browser/chromeos/system/system_clock.h"
 #include "chrome/browser/chromeos/ui/choose_mobile_network_dialog.h"
+#include "chrome/browser/lifetime/application_lifetime.h"
 #include "chrome/browser/profiles/profile_manager.h"
 #include "chrome/browser/ui/ash/ash_util.h"
 #include "chrome/browser/ui/chrome_pages.h"
@@ -277,6 +278,15 @@ void SystemTrayClient::ShowProxySettings() {
   chromeos::LoginDisplayHost::default_host()->OpenProxySettings();
 }
 
+void SystemTrayClient::SignOut() {
+  chrome::AttemptUserExit();
+}
+
+void SystemTrayClient::RequestRestartForUpdate() {
+  // We expect that UpdateEngine is in "Reboot for update" state now.
+  chrome::NotifyAndTerminate(true /* fast_path */);
+}
+
 ////////////////////////////////////////////////////////////////////////////////
 // chromeos::system::SystemClockObserver: