Added an error message when local state corruption is detected.

chrome/browser/prefs/chrome_pref_service_factory.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/prefs/chrome_pref_service_factory.h"
 
 #include <string>
 #include <vector>
 
 #include "base/bind.h"
@@ skipping 289 matching lines @@
       // Specifically enable extension settings enforcement.
       data.enforcement_level = PrefHashFilter::ENFORCE_ON_LOAD;
     }
 #endif
 
     result.push_back(data);
   }
   return result;
 }
 
-
 // Shows notifications which correspond to PersistentPrefStore's reading errors.
 void HandleReadError(PersistentPrefStore::PrefReadError error) {
+  if (error != PersistentPrefStore::PREF_READ_ERROR_NONE &&
+      error != PersistentPrefStore::PREF_READ_ERROR_NO_FILE) {
+    LOG(ERROR) << "An error happened during prefs loading: " << error;
+  }
+
   // Sample the histogram also for the successful case in order to get a
   // baseline on the success rate in addition to the error distribution.
   UMA_HISTOGRAM_ENUMERATION("PrefService.ReadError", error,
                             PersistentPrefStore::PREF_READ_ERROR_MAX_ENUM);
 
   if (error != PersistentPrefStore::PREF_READ_ERROR_NONE) {
 #if !defined(OS_CHROMEOS)
     // Failing to load prefs on startup is a bad thing(TM). See bug 38352 for
     // an example problem that this can cause.
     // Do some diagnosis and try to avoid losing data.
     int message_id = 0;
     if (error <= PersistentPrefStore::PREF_READ_ERROR_JSON_TYPE ||
         error == PersistentPrefStore::PREF_READ_ERROR_LEVELDB_CORRUPTION) {
       message_id = IDS_PREFERENCES_CORRUPT_ERROR;
     } else if (error != PersistentPrefStore::PREF_READ_ERROR_NO_FILE) {
       message_id = IDS_PREFERENCES_UNREADABLE_ERROR;
     }
 
     if (message_id) {
       BrowserThread::PostTask(BrowserThread::UI, FROM_HERE,
                               base::Bind(&ShowProfileErrorDialog,
                                          PROFILE_ERROR_PREFERENCES,
                                          message_id));
     }
 #else
     // On ChromeOS error screen with message about broken local state
     // will be displayed.

[Bernhard Bauer, 2014/09/15 11:41:33]

Shouldn't this take care of broken Local State?

[ygorshenin1, 2014/09/15 12:54:59]

Recovery logic (on OOBE/login screen) is here:
https://code.google.com/p/chromium/codesearch#chromium/src/chrome/browser/chr....

[Bernhard Bauer, 2014/09/15 13:32:09]

So, there is code that shows an error if Local State is broken? What do we need
the log statement for then? I'm confused...

 #endif
   }
 }
 
 scoped_ptr<ProfilePrefStoreManager> CreateProfilePrefStoreManager(
     const base::FilePath& profile_path) {
   std::string device_id;
 #if defined(OS_WIN) && defined(ENABLE_RLZ)
   // This is used by
   // chrome/browser/extensions/api/music_manager_private/device_id_win.cc
@@ skipping 167 matching lines @@
 
 void RegisterProfilePrefs(user_prefs::PrefRegistrySyncable* registry) {
   ProfilePrefStoreManager::RegisterProfilePrefs(registry);
 }
 
 void RegisterPrefs(PrefRegistrySimple* registry) {
   ProfilePrefStoreManager::RegisterPrefs(registry);
 }
 
 }  // namespace chrome_prefs