Added processing for a lost status to UpdateEngineClient.

chrome/browser/extensions/api/system_private/system_private_api.cc

 // Copyright (c) 2012 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/extensions/api/system_private/system_private_api.h"
 
 #include "base/prefs/pref_service.h"
 #include "base/values.h"
 #include "chrome/browser/browser_process.h"
 #include "chrome/browser/extensions/event_router_forwarder.h"
@@ skipping 98 matching lines @@
       state = kUpdatingState;
       download_progress = 1;
       break;
     case chromeos::UpdateEngineClient::UPDATE_STATUS_UPDATED_NEED_REBOOT:
       state = kNeedRestartState;
       download_progress = 1;
       break;
     case chromeos::UpdateEngineClient::UPDATE_STATUS_REPORTING_ERROR_EVENT:
       state = kNotAvailableState;
       break;
+    case chromeos::UpdateEngineClient::UPDATE_STATUS_ATTEMPTING_ROLLBACK:

[Daniel Erat, 2014/06/02 13:41:31]

nit: just combine this with the previous case?

+      state = kNotAvailableState;
+      break;
   }
 #else
   if (UpgradeDetector::GetInstance()->notify_upgrade()) {
     state = kNeedRestartState;
     download_progress = 1;
   } else {
     state = kNotAvailableState;
   }
 #endif
   base::DictionaryValue* dict = new base::DictionaryValue();
@@ skipping 25 matching lines @@
 
 void DispatchScreenUnlockedEvent() {
   DispatchEvent(system_private::OnScreenUnlocked::kEventName, NULL);
 }
 
 void DispatchWokeUpEvent() {
   DispatchEvent(system_private::OnWokeUp::kEventName, NULL);
 }
 
 }  // namespace extensions