kiosk: Add kiosk.always_update manifest key

chrome/browser/chromeos/app_mode/kiosk_app_manager.cc

 // 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.
 
 #include "chrome/browser/chromeos/app_mode/kiosk_app_manager.h"
 
 #include <stddef.h>
 
 #include <utility>
 
@@ skipping 635 matching lines @@
     const extensions::Extension* app) const {
   // Compliant if the app is not the auto launched with zero delay app.
   if (currently_auto_launched_with_zero_delay_app_ != app->id())
     return true;
 
   // Compliant if the app does not specify required platform version.
   const extensions::KioskModeInfo* info = extensions::KioskModeInfo::Get(app);
   if (info == nullptr)
     return true;
 
+  // Compliant if the app wants to be always updated.
+  if (info->always_update)
+    return true;
+
   return IsPlatformCompliant(info->required_platform_version);
 }
 
 KioskAppManager::KioskAppManager()
     : ownership_established_(false),
       external_loader_created_(false),
       secondary_app_external_loader_created_(false) {
   base::FilePath cache_dir;
   GetCrxCacheDir(&cache_dir);
   external_cache_.reset(
@@ skipping 228 matching lines @@
 base::TimeDelta KioskAppManager::GetAutoLaunchDelay() const {
   int delay;
   if (!CrosSettings::Get()->GetInteger(
           kAccountsPrefDeviceLocalAccountAutoLoginDelay, &delay)) {
     return base::TimeDelta();  // Default delay is 0ms.
   }
   return base::TimeDelta::FromMilliseconds(delay);
 }
 
 }  // namespace chromeos