Add ARC++ kiosk menu items and ability to start kiosk session.

chrome/browser/ui/webui/chromeos/login/signin_screen_handler.h

Index: chrome/browser/ui/webui/chromeos/login/signin_screen_handler.h
diff --git a/chrome/browser/ui/webui/chromeos/login/signin_screen_handler.h b/chrome/browser/ui/webui/chromeos/login/signin_screen_handler.h
index 385979c0dfea4f17d2971fdce3f6da89a9070025..004400d6cb536d3b86f0bcd2b40e8d65d45355b3 100644
--- a/chrome/browser/ui/webui/chromeos/login/signin_screen_handler.h
+++ b/chrome/browser/ui/webui/chromeos/login/signin_screen_handler.h
@@ -377,6 +377,7 @@ class SigninScreenHandler
   void HandleHardlockPod(const std::string& user_id);
   void HandleLaunchKioskApp(const AccountId& app_account_id,
                             bool diagnostic_mode);
+  void HandleLaunchArcKioskApp(const AccountId& app_account_id);
   void HandleGetPublicSessionKeyboardLayouts(const AccountId& account_id,
                                              const std::string& locale);
   void HandleGetTouchViewState();