Revert of Let SyncBackupManager keep backup data in memory until shutdown. Only persist

sync/internal_api/sync_backup_manager.cc

Index: sync/internal_api/sync_backup_manager.cc
diff --git a/sync/internal_api/sync_backup_manager.cc b/sync/internal_api/sync_backup_manager.cc
index d626229dfc2760cdf888eda04c1b599d0c0ee335..be8b8720044248a403e928205334745f7d9bacfa 100644
--- a/sync/internal_api/sync_backup_manager.cc
+++ b/sync/internal_api/sync_backup_manager.cc
@@ -23,7 +23,6 @@
   if (SyncRollbackManagerBase::InitInternal(
           args->database_location,
           args->internal_components_factory.get(),
-          InternalComponentsFactory::STORAGE_ON_DISK_DEFERRED,
           args->unrecoverable_error_handler.Pass(),
           args->report_unrecoverable_error_function)) {
     GetUserShare()->directory->CollectMetaHandleCounts(
@@ -35,8 +34,10 @@
 }
 
 void SyncBackupManager::SaveChanges() {
-  if (initialized())
+  if (initialized()) {
     NormalizeEntries();
+    GetUserShare()->directory->SaveChanges();
+  }
 }
 
 SyncStatus SyncBackupManager::GetDetailedStatus() const {
@@ -121,15 +122,6 @@
   }
 }
 
-void SyncBackupManager::ShutdownOnSyncThread(ShutdownReason reason) {
-  if (reason == SWITCH_MODE_SYNC) {
-    NormalizeEntries();
-    GetUserShare()->directory->SaveChanges();
-  }
-
-  SyncRollbackManagerBase::ShutdownOnSyncThread(reason);
-}
-
 void SyncBackupManager::RegisterDirectoryTypeDebugInfoObserver(
     syncer::TypeDebugInfoObserver* observer) {}