Sync: Avoid 3 passes over SyncDarta DB when loading the directory from the disk

sync/syncable/invalid_directory_backing_store.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 "sync/syncable/invalid_directory_backing_store.h"
 
 namespace syncer {
 namespace syncable {
 
 InvalidDirectoryBackingStore::InvalidDirectoryBackingStore()
     : DirectoryBackingStore("some_fake_user") {
 }
 
 InvalidDirectoryBackingStore::~InvalidDirectoryBackingStore() {
 }
 
 DirOpenResult InvalidDirectoryBackingStore::Load(
     Directory::MetahandlesMap* handles_map,
     JournalIndex* delete_journals,
+    MetahandleSet* metahandles_to_purge,
     Directory::KernelLoadInfo* kernel_load_info) {
   return FAILED_OPEN_DATABASE;
 }
 
 }  // namespace syncable
 }  // namespace syncer