Install and launch kiosk app from cached crx file at start up.

chrome/browser/chromeos/app_mode/kiosk_app_launch_error.h

 // Copyright 2013 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_APP_MODE_KIOSK_APP_LAUNCH_ERROR_H_
 #define CHROME_BROWSER_CHROMEOS_APP_MODE_KIOSK_APP_LAUNCH_ERROR_H_
 
 #include <string>
 
 #include "base/basictypes.h"
 
 namespace chromeos {
 
 class KioskAppLaunchError {
  public:
   enum Error {
     NONE,                     // No error.
     HAS_PENDING_LAUNCH,       // There is a pending launch already.
     CRYPTOHOMED_NOT_RUNNING,  // Unable to call cryptohome daemon.
     ALREADY_MOUNTED,          // Cryptohome is already mounted.
     UNABLE_TO_MOUNT,          // Unable to mount cryptohome.
     UNABLE_TO_REMOVE,         // Unable to remove cryptohome.
     UNABLE_TO_INSTALL,        // Unable to install app.
+    UNABLE_TO_DOWNLOAD,       // Unalbe to download app's crx file.
+    UNABLE_TO_LAUNCH,         // Unable to launch app.

[xiyuan, 2014/05/29 19:49:01]

Append to the end so that existing enums still have the same numeric number.

[jennyz, 2014/07/07 21:11:12]

Done.

     USER_CANCEL,              // Canceled by user.
     NOT_KIOSK_ENABLED,        // Not a kiosk enabled app.
     UNABLE_TO_RETRIEVE_HASH,  // Unable to retrieve username hash.
     POLICY_LOAD_FAILED,       // Failed to load policy for kiosk account.
   };
 
   // Returns a message for given |error|.
   static std::string GetErrorMessage(Error error);
 
   // Save error for displaying on next restart. Note only the last saved error
   // will be kept.
   static void Save(Error error);
 
   // Gets the saved error.
   static Error Get();
 
   // Clears the saved error.
   static void Clear();
 
  private:
   DISALLOW_IMPLICIT_CONSTRUCTORS(KioskAppLaunchError);
 };
 
 }  // namespace chromeos
 
 #endif  // CHROME_BROWSER_CHROMEOS_APP_MODE_KIOSK_APP_LAUNCH_ERROR_H_