Don't activate a window if screen is locked.

chrome/browser/chromeos/login/base_login_display_host.h

 // Copyright (c) 2011 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_LOGIN_BASE_LOGIN_DISPLAY_HOST_H_
 #define CHROME_BROWSER_CHROMEOS_LOGIN_BASE_LOGIN_DISPLAY_HOST_H_
 #pragma once
 
 #include <string>
 
@@ skipping 35 matching lines @@
   // Returns the default LoginDispalyHost instance if it has been created.
   static LoginDisplayHost* default_host() {
     return default_host_;
   }
 
   // Registers preferences in local state.
   static void RegisterPrefs(PrefService* local_state);
 
   // LoginDisplayHost implementation:
   virtual void OnSessionStart() OVERRIDE;
+  virtual void PreSessionStart() OVERRIDE;
   virtual void StartWizard(
       const std::string& first_screen_name,
       DictionaryValue* screen_parameters) OVERRIDE;
   virtual void StartSignInScreen() OVERRIDE;
   virtual void ResumeSignInScreen() OVERRIDE;
   virtual void CheckForAutoEnrollment() OVERRIDE;
 
   // Creates specific WizardController.
   virtual WizardController* CreateWizardController() = 0;
 
@@ skipping 51 matching lines @@
 
   // Used to verify if the device has already been owned.
   scoped_ptr<OwnershipStatusChecker> ownership_status_checker_;
 
   DISALLOW_COPY_AND_ASSIGN(BaseLoginDisplayHost);
 };
 
 }  // namespace chromeos
 
 #endif  // CHROME_BROWSER_CHROMEOS_LOGIN_BASE_LOGIN_DISPLAY_HOST_H_