[Sync] Fix bug where DeviceInfo is missing a backup timestamp

chrome/browser/sync/profile_sync_service.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/sync/profile_sync_service.h"
 
 #include <cstddef>
 #include <map>
 #include <vector>
 
@@ skipping 292 matching lines @@
 
   RegisterAuthNotifications();
 
   if (!HasSyncSetupCompleted() || signin_->GetEffectiveUsername().empty()) {
     // Clean up in case of previous crash / setup abort / signout.
     DisableForUser();
   }
 
   TrySyncDatatypePrefRecovery();
 
-  last_synced_time_ = sync_prefs_.GetLastSyncedTime();
-
 #if defined(OS_CHROMEOS)
   std::string bootstrap_token = sync_prefs_.GetEncryptionBootstrapToken();
   if (bootstrap_token.empty()) {
     sync_prefs_.SetEncryptionBootstrapToken(
         sync_prefs_.GetSpareBootstrapToken());
   }
 #endif
 
 #if !defined(OS_ANDROID)
   DCHECK(sync_error_controller_ == NULL)
@@ skipping 577 matching lines @@
 
 bool ProfileSyncService::HasSyncSetupCompleted() const {
   return sync_prefs_.HasSyncSetupCompleted();
 }
 
 void ProfileSyncService::SetSyncSetupCompleted() {
   sync_prefs_.SetSyncSetupCompleted();
 }
 
 void ProfileSyncService::UpdateLastSyncedTime() {
-  last_synced_time_ = base::Time::Now();
-  sync_prefs_.SetLastSyncedTime(last_synced_time_);
+  sync_prefs_.SetLastSyncedTime(base::Time::Now());
 }
 
 void ProfileSyncService::NotifyObservers() {
   FOR_EACH_OBSERVER(ProfileSyncServiceBase::Observer, observers_,
                     OnStateChanged());
 }
 
 void ProfileSyncService::NotifySyncCycleCompleted() {
   FOR_EACH_OBSERVER(ProfileSyncServiceBase::Observer, observers_,
                     OnSyncCycleCompleted());
@@ skipping 103 matching lines @@
   if (type_debug_info_observers_.might_have_observers()) {
     backend_->EnableDirectoryTypeDebugInfoForwarding();
   }
 
   // If we have a cached passphrase use it to decrypt/encrypt data now that the
   // backend is initialized. We want to call this before notifying observers in
   // case this operation affects the "passphrase required" status.
   ConsumeCachedPassphraseIfPossible();
 
   // The very first time the backend initializes is effectively the first time
-  // we can say we successfully "synced".  last_synced_time_ will only be null
-  // in this case, because the pref wasn't restored on StartUp.
-  if (last_synced_time_.is_null()) {
+  // we can say we successfully "synced".  LastSyncedTime will only be null in
+  // this case, because the pref wasn't restored on StartUp.
+  if (sync_prefs_.GetLastSyncedTime().is_null()) {
     UpdateLastSyncedTime();
   }
 
   if (startup_controller_.auto_start_enabled() && !FirstSetupInProgress()) {
     // Backend is initialized but we're not in sync setup, so this must be an
     // autostart - mark our sync setup as completed and we'll start syncing
     // below.
     SetSyncSetupCompleted();
   }
 
@@ skipping 649 matching lines @@
 }
 
 bool ProfileSyncService::IsPassphraseRequiredForDecryption() const {
   // If there is an encrypted datatype enabled and we don't have the proper
   // passphrase, we must prompt the user for a passphrase. The only way for the
   // user to avoid entering their passphrase is to disable the encrypted types.
   return IsEncryptedDatatypeEnabled() && IsPassphraseRequired();
 }
 
 base::string16 ProfileSyncService::GetLastSyncedTimeString() const {
-  if (last_synced_time_.is_null())
+  const base::Time last_synced_time = sync_prefs_.GetLastSyncedTime();
+  if (last_synced_time.is_null())
     return l10n_util::GetStringUTF16(IDS_SYNC_TIME_NEVER);
 
-  base::TimeDelta last_synced = base::Time::Now() - last_synced_time_;
+  base::TimeDelta time_since_last_sync = base::Time::Now() - last_synced_time;
 
-  if (last_synced < base::TimeDelta::FromMinutes(1))
+  if (time_since_last_sync < base::TimeDelta::FromMinutes(1))
     return l10n_util::GetStringUTF16(IDS_SYNC_TIME_JUST_NOW);
 
   return ui::TimeFormat::Simple(ui::TimeFormat::FORMAT_ELAPSED,
-                                ui::TimeFormat::LENGTH_SHORT, last_synced);
+                                ui::TimeFormat::LENGTH_SHORT,
+                                time_since_last_sync);
 }
 
 void ProfileSyncService::UpdateSelectedTypesHistogram(
     bool sync_everything, const syncer::ModelTypeSet chosen_types) const {
   if (!HasSyncSetupCompleted() ||
       sync_everything != sync_prefs_.HasKeepEverythingSynced()) {
     UMA_HISTOGRAM_BOOLEAN("Sync.SyncEverything", sync_everything);
   }
 
   // Only log the data types that are shown in the sync settings ui.
@@ skipping 950 matching lines @@
       }
     }
   }
   return result;
 }
 
 void ProfileSyncService::CheckSyncBackupIfNeeded() {
   DCHECK_EQ(backend_mode_, SYNC);
 
 #if defined(ENABLE_PRE_SYNC_BACKUP)
+  const base::Time last_synced_time = sync_prefs_.GetLastSyncedTime();
   // Check backup once a day.
   if (!last_backup_time_ &&
-      (last_synced_time_.is_null() ||
-          base::Time::Now() - last_synced_time_ >=
+      (last_synced_time.is_null() ||
+          base::Time::Now() - last_synced_time >=
               base::TimeDelta::FromDays(1))) {
     // If sync thread is set, need to serialize check on sync thread after
     // closing backup DB.
     if (sync_thread_) {
       sync_thread_->message_loop_proxy()->PostTask(
           FROM_HERE,
           base::Bind(syncer::CheckSyncDbLastModifiedTime,
                      profile_->GetPath().Append(kSyncBackupDataFolderName),
                      base::MessageLoopProxy::current(),
                      base::Bind(&ProfileSyncService::CheckSyncBackupCallback,
@@ skipping 32 matching lines @@
                  true));
 }
 
 bool ProfileSyncService::NeedBackup() const {
   return need_backup_;
 }
 
 base::Time ProfileSyncService::GetDeviceBackupTimeForTesting() const {
   return device_info_sync_service_->GetLocalDeviceBackupTime();
 }