[Sync] Remove backup/rollback logic from Sync

BUG=586596

Review URL: https://codereview.chromium.org/1703173002

Cr-Commit-Position: refs/heads/master@{#377370}

32 files changed, 11 insertions, 1755 deletions

diff --git a/sync/BUILD.gn b/sync/BUILD.gn
index dfa0fae..f28fee8 100644
--- a/sync/BUILD.gn
+++ b/sync/BUILD.gn
@@ -297,8 +297,6 @@ source_set("sync_core") {
     "internal_api/read_node.cc",
     "internal_api/read_transaction.cc",
     "internal_api/shared_model_type_processor.cc",
-    "internal_api/sync_backup_manager.cc",
-    "internal_api/sync_backup_manager.h",
     "internal_api/sync_context.cc",
     "internal_api/sync_context_proxy.cc",
     "internal_api/sync_context_proxy_impl.cc",
@@ -309,10 +307,6 @@ source_set("sync_core") {
     "internal_api/sync_manager_factory.cc",
     "internal_api/sync_manager_impl.cc",
     "internal_api/sync_manager_impl.h",
-    "internal_api/sync_rollback_manager.cc",
-    "internal_api/sync_rollback_manager.h",
-    "internal_api/sync_rollback_manager_base.cc",
-    "internal_api/sync_rollback_manager_base.h",
     "internal_api/syncapi_internal.cc",
     "internal_api/syncapi_internal.h",
     "internal_api/syncapi_server_connection_manager.cc",
@@ -348,8 +342,6 @@ source_set("sync_core") {
     "sessions/sync_session.h",
     "sessions/sync_session_context.cc",
     "sessions/sync_session_context.h",
-    "syncable/deferred_on_disk_directory_backing_store.cc",
-    "syncable/deferred_on_disk_directory_backing_store.h",
     "syncable/dir_open_result.h",
     "syncable/directory.cc",
     "syncable/directory.h",
@@ -666,12 +658,9 @@ test("sync_unit_tests") {
     "internal_api/public/util/proto_value_ptr_unittest.cc",
     "internal_api/public/util/weak_handle_unittest.cc",
     "internal_api/shared_model_type_processor_unittest.cc",
-    "internal_api/sync_backup_manager_unittest.cc",
     "internal_api/sync_context_proxy_impl_unittest.cc",
     "internal_api/sync_encryption_handler_impl_unittest.cc",
     "internal_api/sync_manager_impl_unittest.cc",
-    "internal_api/sync_rollback_manager_base_unittest.cc",
-    "internal_api/sync_rollback_manager_unittest.cc",
     "internal_api/syncapi_server_connection_manager_unittest.cc",
     "js/js_event_details_unittest.cc",
     "js/sync_js_controller_unittest.cc",
@@ -680,7 +669,6 @@ test("sync_unit_tests") {
     "sessions/model_type_registry_unittest.cc",
     "sessions/nudge_tracker_unittest.cc",
     "sessions/status_controller_unittest.cc",
-    "syncable/deferred_on_disk_directory_backing_store_unittest.cc",
     "syncable/directory_backing_store_unittest.cc",
     "syncable/directory_unittest.cc",
     "syncable/directory_unittest.h",
diff --git a/sync/engine/sync_scheduler_impl.cc b/sync/engine/sync_scheduler_impl.cc
index f126473..cc5e4a7 100644
--- a/sync/engine/sync_scheduler_impl.cc
+++ b/sync/engine/sync_scheduler_impl.cc
@@ -58,7 +58,6 @@ bool ShouldRequestEarlyExit(const SyncProtocolError& error) {
     case CLIENT_DATA_OBSOLETE:
     case CLEAR_PENDING:
     case DISABLED_BY_ADMIN:
-    case USER_ROLLBACK:
       // If we send terminate sync early then |sync_cycle_ended| notification
       // would not be sent. If there were no actions then |ACTIONABLE_ERROR|
       // notification wouldnt be sent either. Then the UI layer would be left
diff --git a/sync/engine/syncer_proto_util.cc b/sync/engine/syncer_proto_util.cc
index 306137b..66c4013 100644
--- a/sync/engine/syncer_proto_util.cc
+++ b/sync/engine/syncer_proto_util.cc
@@ -124,8 +124,6 @@ SyncProtocolErrorType PBErrorTypeToSyncProtocolErrorType(
       return MIGRATION_DONE;
     case sync_pb::SyncEnums::DISABLED_BY_ADMIN:
       return DISABLED_BY_ADMIN;
-    case sync_pb::SyncEnums::USER_ROLLBACK:
-      return USER_ROLLBACK;
     case sync_pb::SyncEnums::PARTIAL_FAILURE:
       return PARTIAL_FAILURE;
     case sync_pb::SyncEnums::CLIENT_DATA_OBSOLETE:
@@ -193,8 +191,6 @@ SyncProtocolError ErrorCodeToSyncProtocolError(
     error.action = RESET_LOCAL_SYNC_DATA;
   } else if (error_type == sync_pb::SyncEnums::DISABLED_BY_ADMIN) {
     error.action = STOP_SYNC_FOR_DISABLED_ACCOUNT;
-  } else if (error_type == sync_pb::SyncEnums::USER_ROLLBACK) {
-    error.action = DISABLE_SYNC_AND_ROLLBACK;
   }  // There is no other action we can compute for legacy server.
   return error;
 }
@@ -498,8 +494,6 @@ SyncerError SyncerProtoUtil::PostClientToServerMessage(
       return SERVER_RETURN_NOT_MY_BIRTHDAY;
     case DISABLED_BY_ADMIN:
       return SERVER_RETURN_DISABLED_BY_ADMIN;
-    case USER_ROLLBACK:
-      return SERVER_RETURN_USER_ROLLBACK;
     case PARTIAL_FAILURE:
       // This only happens when partial throttling during GetUpdates.
       if (!sync_protocol_error.error_data_types.Empty()) {
diff --git a/sync/internal_api/internal_components_factory_impl.cc b/sync/internal_api/internal_components_factory_impl.cc
index 4f2f32e..65fcfaf 100644
--- a/sync/internal_api/internal_components_factory_impl.cc
+++ b/sync/internal_api/internal_components_factory_impl.cc
@@ -11,7 +11,6 @@
 #include "sync/engine/syncer.h"
 #include "sync/engine/sync_scheduler_impl.h"
 #include "sync/sessions/sync_session_context.h"
-#include "sync/syncable/deferred_on_disk_directory_backing_store.h"
 #include "sync/syncable/on_disk_directory_backing_store.h"
 
 using base::TimeDelta;
@@ -68,10 +67,6 @@ InternalComponentsFactoryImpl::BuildDirectoryBackingStore(
   if (storage == STORAGE_ON_DISK) {
     return scoped_ptr<syncable::DirectoryBackingStore>(
         new syncable::OnDiskDirectoryBackingStore(dir_name, backing_filepath));
-  } else if (storage == STORAGE_ON_DISK_DEFERRED) {
-    return scoped_ptr<syncable::DirectoryBackingStore>(
-        new syncable::DeferredOnDiskDirectoryBackingStore(dir_name,
-                                                          backing_filepath));
   } else {
     NOTREACHED();
     return scoped_ptr<syncable::DirectoryBackingStore>();
diff --git a/sync/internal_api/public/configure_reason.h b/sync/internal_api/public/configure_reason.h
index 8fbbc4e..4d015b9 100644
--- a/sync/internal_api/public/configure_reason.h
+++ b/sync/internal_api/public/configure_reason.h
@@ -33,9 +33,6 @@ enum ConfigureReason {
   // cryptographer errors/resolutions.
   CONFIGURE_REASON_CRYPTO,
 
-  // Configure data types for backup/rollback.
-  CONFIGURE_REASON_BACKUP_ROLLBACK,
-
   // The client is configuring because of a programmatic type enable/disable,
   // such as when an error is encountered/resolved.
   CONFIGURE_REASON_PROGRAMMATIC,
diff --git a/sync/internal_api/public/internal_components_factory.h b/sync/internal_api/public/internal_components_factory.h
index f077af0..fee9bec 100644
--- a/sync/internal_api/public/internal_components_factory.h
+++ b/sync/internal_api/public/internal_components_factory.h
@@ -80,9 +80,6 @@ class SYNC_EXPORT InternalComponentsFactory {
     // Use this if you want BuildDirectoryBackingStore to create/use a real
     // on disk store.
     STORAGE_ON_DISK,
-    // Use this to defer creating on-disk database until
-    // DirectoryBackingStore::SaveChanges() is called.
-    STORAGE_ON_DISK_DEFERRED,
     // Use this to test the case where a directory fails to load.
     STORAGE_INVALID
   };
diff --git a/sync/internal_api/public/shutdown_reason.h b/sync/internal_api/public/shutdown_reason.h
index f913eec..604dc0e 100644
--- a/sync/internal_api/public/shutdown_reason.h
+++ b/sync/internal_api/public/shutdown_reason.h
@@ -14,8 +14,6 @@ enum ShutdownReason {
   STOP_SYNC,         // Sync is asked to stop, e.g. due to scarce resource.
   DISABLE_SYNC,      // Sync is disabled, e.g. user sign out, dashboard clear.
   BROWSER_SHUTDOWN,  // Browser is closed.
-  SWITCH_MODE_SYNC,  // Engine is shut down and a new engine will start in
-                     // sync mode.
 };
 
 }  // namespace syncer
diff --git a/sync/internal_api/public/sync_manager_factory.h b/sync/internal_api/public/sync_manager_factory.h
index ef6ee6b..feb9e8b 100644
--- a/sync/internal_api/public/sync_manager_factory.h
+++ b/sync/internal_api/public/sync_manager_factory.h
@@ -15,22 +15,15 @@ namespace syncer {
 
 class SyncManager;
 
-// Helper class to allow dependency injection of the SyncManager.
+// Helper class to allow dependency injection of the SyncManager in tests.
 class SYNC_EXPORT SyncManagerFactory {
  public:
-  enum MANAGER_TYPE {
-    NORMAL,     // Normal sync manager
-    BACKUP,     // Backup sync manager
-    ROLLBACK,   // Rollback sync manager
-  };
-
-  explicit SyncManagerFactory(MANAGER_TYPE type);
+  SyncManagerFactory();
   virtual ~SyncManagerFactory();
 
   virtual scoped_ptr<SyncManager> CreateSyncManager(const std::string& name);
 
  private:
-  MANAGER_TYPE type_;
   DISALLOW_COPY_AND_ASSIGN(SyncManagerFactory);
 };
 
diff --git a/sync/internal_api/sync_backup_manager.cc b/sync/internal_api/sync_backup_manager.cc
deleted file mode 100644
index 9151e52..0000000
--- a/sync/internal_api/sync_backup_manager.cc
+++ /dev/null
@@ -1,151 +0,0 @@
-// Copyright 2014 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/internal_api/sync_backup_manager.h"
-
-#include <stdint.h>
-
-#include <vector>
-
-#include "sync/internal_api/public/read_node.h"
-#include "sync/internal_api/public/write_transaction.h"
-#include "sync/syncable/directory.h"
-#include "sync/syncable/mutable_entry.h"
-#include "url/gurl.h"
-
-namespace syncer {
-
-SyncBackupManager::SyncBackupManager()
-    : in_normalization_(false) {
-}
-
-SyncBackupManager::~SyncBackupManager() {
-}
-
-void SyncBackupManager::Init(InitArgs* args) {
-  if (SyncRollbackManagerBase::InitInternal(
-          args->database_location,
-          args->internal_components_factory.get(),
-          InternalComponentsFactory::STORAGE_ON_DISK_DEFERRED,
-          args->unrecoverable_error_handler,
-          args->report_unrecoverable_error_function)) {
-    GetUserShare()->directory->CollectMetaHandleCounts(
-        &status_.num_entries_by_type, &status_.num_to_delete_entries_by_type);
-
-    HideSyncPreference(PRIORITY_PREFERENCES);
-    HideSyncPreference(PREFERENCES);
-  }
-}
-
-void SyncBackupManager::SaveChanges() {
-  if (initialized())
-    NormalizeEntries();
-}
-
-SyncStatus SyncBackupManager::GetDetailedStatus() const {
-  return status_;
-}
-
-ModelTypeSet SyncBackupManager::HandleTransactionEndingChangeEvent(
-    const syncable::ImmutableWriteTransactionInfo& write_transaction_info,
-    syncable::BaseTransaction* trans) {
-  ModelTypeSet types;
-  if (in_normalization_) {
-    // Skip if in our own WriteTransaction from NormalizeEntries().
-    in_normalization_ = false;
-    return types;
-  }
-
-  for (syncable::EntryKernelMutationMap::const_iterator it =
-      write_transaction_info.Get().mutations.Get().begin();
-      it != write_transaction_info.Get().mutations.Get().end(); ++it) {
-    int64_t id = it->first;
-    if (unsynced_.find(id) == unsynced_.end()) {
-      unsynced_.insert(id);
-
-      const syncable::EntryKernel& e = it->second.mutated;
-      ModelType type = e.GetModelType();
-      types.Put(type);
-      if (!e.ref(syncable::ID).ServerKnows())
-        status_.num_entries_by_type[type]++;
-      if (e.ref(syncable::IS_DEL))
-        status_.num_to_delete_entries_by_type[type]++;
-    }
-  }
-  return types;
-}
-
-void SyncBackupManager::NormalizeEntries() {
-  WriteTransaction trans(FROM_HERE, GetUserShare());
-  in_normalization_ = true;
-  for (std::set<int64_t>::const_iterator it = unsynced_.begin();
-       it != unsynced_.end(); ++it) {
-    syncable::MutableEntry entry(trans.GetWrappedWriteTrans(),
-                                 syncable::GET_BY_HANDLE, *it);
-    CHECK(entry.good());
-
-    if (!entry.GetId().ServerKnows())
-      entry.PutId(syncable::Id::CreateFromServerId(entry.GetId().value()));
-    if (!entry.GetParentId().IsNull() && !entry.GetParentId().ServerKnows()) {
-      entry.PutParentIdPropertyOnly(syncable::Id::CreateFromServerId(
-          entry.GetParentId().value()));
-    }
-    entry.PutBaseVersion(1);
-    entry.PutIsUnsynced(false);
-  }
-  unsynced_.clear();
-}
-
-void SyncBackupManager::HideSyncPreference(ModelType type) {
-  WriteTransaction trans(FROM_HERE, GetUserShare());
-  ReadNode pref_root(&trans);
-  if (BaseNode::INIT_OK != pref_root.InitTypeRoot(type))
-    return;
-
-  std::vector<int64_t> pref_ids;
-  pref_root.GetChildIds(&pref_ids);
-  for (uint32_t i = 0; i < pref_ids.size(); ++i) {
-    syncable::MutableEntry entry(trans.GetWrappedWriteTrans(),
-                                 syncable::GET_BY_HANDLE, pref_ids[i]);
-    if (entry.good()) {
-      // HACKY: Set IS_DEL to true to remove entry from parent-children
-      // index so that it's not returned when syncable service asks
-      // for sync data. Syncable service then creates entry for local
-      // model. Then the existing entry is undeleted and set to local value
-      // because it has the same unique client tag.
-      entry.PutIsDel(true);
-      entry.PutIsUnsynced(false);
-
-      // Don't persist on disk so that if backup is aborted before receiving
-      // local preference values, values in sync DB are saved.
-      GetUserShare()->directory->UnmarkDirtyEntry(
-          trans.GetWrappedWriteTrans(), &entry);
-    }
-  }
-}
-
-void SyncBackupManager::ShutdownOnSyncThread(ShutdownReason reason) {
-  if (reason == SWITCH_MODE_SYNC) {
-    NormalizeEntries();
-    GetUserShare()->directory->SaveChanges();
-  }
-
-  SyncRollbackManagerBase::ShutdownOnSyncThread(reason);
-}
-
-void SyncBackupManager::RegisterDirectoryTypeDebugInfoObserver(
-    syncer::TypeDebugInfoObserver* observer) {}
-
-void SyncBackupManager::UnregisterDirectoryTypeDebugInfoObserver(
-    syncer::TypeDebugInfoObserver* observer) {}
-
-bool SyncBackupManager::HasDirectoryTypeDebugInfoObserver(
-    syncer::TypeDebugInfoObserver* observer) { return false; }
-
-void SyncBackupManager::RequestEmitDebugInfo() {}
-
-void SyncBackupManager::ClearServerData(
-    const ClearServerDataCallback& callback) {}
-
-}  // namespace syncer
diff --git a/sync/internal_api/sync_backup_manager.h b/sync/internal_api/sync_backup_manager.h
deleted file mode 100644
index e7e50fa..0000000
--- a/sync/internal_api/sync_backup_manager.h
+++ /dev/null
@@ -1,70 +0,0 @@
-// Copyright 2014 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.
-
-#ifndef SYNC_INTERNAL_API_SYNC_BACKUP_MANAGER_H_
-#define SYNC_INTERNAL_API_SYNC_BACKUP_MANAGER_H_
-
-#include <stdint.h>
-
-#include <set>
-
-#include "base/macros.h"
-#include "sync/internal_api/sync_rollback_manager_base.h"
-#include "url/gurl.h"
-
-namespace syncer {
-
-// SyncBackupManager runs before user signs in to sync to back up user's data
-// before sync starts. The data that's backed up can be used to restore user's
-// settings to pre-sync state.
-class SYNC_EXPORT SyncBackupManager : public SyncRollbackManagerBase {
- public:
-  SyncBackupManager();
-  ~SyncBackupManager() override;
-
-  // SyncManager implementation.
-  void Init(InitArgs* args) override;
-  void SaveChanges() override;
-  SyncStatus GetDetailedStatus() const override;
-  void ShutdownOnSyncThread(ShutdownReason reason) override;
-
-  // DirectoryChangeDelegate implementation.
-  ModelTypeSet HandleTransactionEndingChangeEvent(
-      const syncable::ImmutableWriteTransactionInfo& write_transaction_info,
-      syncable::BaseTransaction* trans) override;
-
-  void RegisterDirectoryTypeDebugInfoObserver(
-      syncer::TypeDebugInfoObserver* observer) override;
-  void UnregisterDirectoryTypeDebugInfoObserver(
-      syncer::TypeDebugInfoObserver* observer) override;
-  bool HasDirectoryTypeDebugInfoObserver(
-      syncer::TypeDebugInfoObserver* observer) override;
-  void RequestEmitDebugInfo() override;
-  void ClearServerData(const ClearServerDataCallback& callback) override;
-
- private:
-  // Replaces local IDs with server IDs and clear unsynced bit of modified
-  // entries.
-  void NormalizeEntries();
-
-  // Manipulate preference nodes so that they'll be overwritten by local
-  // preference values during model association, i.e. local wins instead of
-  // server wins. This is for preventing backup from changing preferences in
-  // case backup DB has hijacked preferences.
-  void HideSyncPreference(ModelType pref_type);
-
-  // Handles of unsynced entries caused by local model changes.
-  std::set<int64_t> unsynced_;
-
-  // True if NormalizeEntries() is being called.
-  bool in_normalization_;
-
-  SyncStatus status_;
-
-  DISALLOW_COPY_AND_ASSIGN(SyncBackupManager);
-};
-
-}  // namespace syncer
-
-#endif  // SYNC_INTERNAL_API_SYNC_BACKUP_MANAGER_H_
diff --git a/sync/internal_api/sync_backup_manager_unittest.cc b/sync/internal_api/sync_backup_manager_unittest.cc
deleted file mode 100644
index 919356d..0000000
--- a/sync/internal_api/sync_backup_manager_unittest.cc
+++ /dev/null
@@ -1,185 +0,0 @@
-// Copyright 2014 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/internal_api/sync_backup_manager.h"
-
-#include <string>
-
-#include "base/files/scoped_temp_dir.h"
-#include "base/run_loop.h"
-#include "sync/internal_api/public/read_node.h"
-#include "sync/internal_api/public/read_transaction.h"
-#include "sync/internal_api/public/sessions/sync_session_snapshot.h"
-#include "sync/internal_api/public/test/test_internal_components_factory.h"
-#include "sync/internal_api/public/write_node.h"
-#include "sync/internal_api/public/write_transaction.h"
-#include "sync/syncable/entry.h"
-#include "sync/test/test_directory_backing_store.h"
-#include "testing/gmock/include/gmock/gmock.h"
-#include "testing/gtest/include/gtest/gtest.h"
-#include "url/gurl.h"
-
-using ::testing::_;
-using ::testing::Invoke;
-using ::testing::WithArgs;
-
-namespace syncer {
-
-namespace {
-
-void OnConfigDone(bool success) {
-  EXPECT_TRUE(success);
-}
-
-class SyncBackupManagerTest : public syncer::SyncManager::Observer,
-                              public testing::Test {
- public:
-  MOCK_METHOD1(OnSyncCycleCompleted,
-               void(const sessions::SyncSessionSnapshot&));
-  MOCK_METHOD1(OnConnectionStatusChange, void(ConnectionStatus));
-  MOCK_METHOD1(OnActionableError, void(const SyncProtocolError&));
-  MOCK_METHOD1(OnMigrationRequested, void(ModelTypeSet));
-  MOCK_METHOD1(OnProtocolEvent, void(const ProtocolEvent&));
-  MOCK_METHOD4(OnInitializationComplete,
-               void(const WeakHandle<JsBackend>&,
-                    const WeakHandle<DataTypeDebugInfoListener>&,
-                    bool, ModelTypeSet));
-
- protected:
-  void SetUp() override {
-    CHECK(temp_dir_.CreateUniqueTempDir());
-  }
-
-  void InitManager(SyncManager* manager,
-                   InternalComponentsFactory::StorageOption storage_option) {
-    manager_ = manager;
-    EXPECT_CALL(*this, OnInitializationComplete(_, _, _, _))
-        .WillOnce(WithArgs<2>(Invoke(this,
-                                     &SyncBackupManagerTest::HandleInit)));
-
-    manager->AddObserver(this);
-
-    base::RunLoop run_loop;
-
-    SyncManager::InitArgs args;
-    args.database_location = temp_dir_.path();
-    args.event_handler = MakeWeakHandle(base::WeakPtr<JsEventHandler>());
-    args.service_url = GURL("https://example.com/");
-    args.post_factory = scoped_ptr<HttpPostProviderFactory>();
-    args.internal_components_factory.reset(new TestInternalComponentsFactory(
-        InternalComponentsFactory::Switches(), storage_option,
-        &storage_used_));
-    manager->Init(&args);
-    EXPECT_EQ(InternalComponentsFactory::STORAGE_ON_DISK_DEFERRED,
-              storage_used_);
-    loop_.PostTask(FROM_HERE, run_loop.QuitClosure());
-    run_loop.Run();
-  }
-
-  void CreateEntry(UserShare* user_share, ModelType type,
-                   const std::string& client_tag) {
-    WriteTransaction trans(FROM_HERE, user_share);
-
-    WriteNode node(&trans);
-    EXPECT_EQ(WriteNode::INIT_SUCCESS,
-              node.InitUniqueByCreation(type, client_tag));
-  }
-
-  void ConfigureSyncer() {
-    manager_->ConfigureSyncer(CONFIGURE_REASON_NEW_CLIENT,
-                              ModelTypeSet(SEARCH_ENGINES),
-                              ModelTypeSet(), ModelTypeSet(), ModelTypeSet(),
-                              ModelSafeRoutingInfo(),
-                              base::Bind(&OnConfigDone, true),
-                              base::Bind(&OnConfigDone, false));
-  }
-
-  void HandleInit(bool success) {
-    if (success) {
-      loop_.PostTask(FROM_HERE,
-                     base::Bind(&SyncBackupManagerTest::ConfigureSyncer,
-                                base::Unretained(this)));
-    } else {
-      manager_->ShutdownOnSyncThread(STOP_SYNC);
-    }
-  }
-
-  base::ScopedTempDir temp_dir_;
-  base::MessageLoop loop_;    // Needed for WeakHandle
-  SyncManager* manager_;
-  InternalComponentsFactory::StorageOption storage_used_;
-};
-
-TEST_F(SyncBackupManagerTest, NormalizeEntry) {
-  scoped_ptr<SyncBackupManager> manager(new SyncBackupManager);
-  InitManager(manager.get(), InternalComponentsFactory::STORAGE_IN_MEMORY);
-
-  CreateEntry(manager->GetUserShare(), SEARCH_ENGINES, "test");
-
-  {
-    // New entry is local and unsynced at first.
-    ReadTransaction trans(FROM_HERE, manager->GetUserShare());
-    ReadNode pref(&trans);
-    EXPECT_EQ(BaseNode::INIT_OK,
-              pref.InitByClientTagLookup(SEARCH_ENGINES, "test"));
-    EXPECT_FALSE(pref.GetEntry()->GetId().ServerKnows());
-    EXPECT_TRUE(pref.GetEntry()->GetIsUnsynced());
-  }
-
-  manager->SaveChanges();
-
-  {
-    // New entry has server ID and unsynced bit is cleared after saving.
-    ReadTransaction trans(FROM_HERE, manager->GetUserShare());
-    ReadNode pref(&trans);
-    EXPECT_EQ(BaseNode::INIT_OK,
-              pref.InitByClientTagLookup(SEARCH_ENGINES, "test"));
-    EXPECT_TRUE(pref.GetEntry()->GetId().ServerKnows());
-    EXPECT_FALSE(pref.GetEntry()->GetIsUnsynced());
-  }
-}
-
-TEST_F(SyncBackupManagerTest, PersistWithSwitchToSyncShutdown) {
-  scoped_ptr<SyncBackupManager> manager(new SyncBackupManager);
-  InitManager(manager.get(),
-              InternalComponentsFactory::STORAGE_ON_DISK_DEFERRED);
-
-  CreateEntry(manager->GetUserShare(), SEARCH_ENGINES, "test");
-  manager->SaveChanges();
-  manager->ShutdownOnSyncThread(SWITCH_MODE_SYNC);
-
-  // Reopen db to verify entry is persisted.
-  manager.reset(new SyncBackupManager);
-  InitManager(manager.get(), InternalComponentsFactory::STORAGE_ON_DISK);
-  {
-    ReadTransaction trans(FROM_HERE, manager->GetUserShare());
-    ReadNode pref(&trans);
-    EXPECT_EQ(BaseNode::INIT_OK,
-              pref.InitByClientTagLookup(SEARCH_ENGINES, "test"));
-    EXPECT_TRUE(pref.GetEntry()->GetId().ServerKnows());
-    EXPECT_FALSE(pref.GetEntry()->GetIsUnsynced());
-  }
-}
-
-TEST_F(SyncBackupManagerTest, DontPersistWithOtherShutdown) {
-  scoped_ptr<SyncBackupManager> manager(new SyncBackupManager);
-  InitManager(manager.get(),
-              InternalComponentsFactory::STORAGE_ON_DISK_DEFERRED);
-
-  CreateEntry(manager->GetUserShare(), SEARCH_ENGINES, "test");
-  manager->SaveChanges();
-  manager->ShutdownOnSyncThread(STOP_SYNC);
-  EXPECT_FALSE(base::PathExists(
-      temp_dir_.path().Append(syncable::Directory::kSyncDatabaseFilename)));
-}
-
-TEST_F(SyncBackupManagerTest, FailToInitialize) {
-  // Test graceful shutdown on initialization failure.
-  scoped_ptr<SyncBackupManager> manager(new SyncBackupManager);
-  InitManager(manager.get(), InternalComponentsFactory::STORAGE_INVALID);
-}
-
-}  // anonymous namespace
-
-}  // namespace syncer
diff --git a/sync/internal_api/sync_manager_factory.cc b/sync/internal_api/sync_manager_factory.cc
index 288b5da..48ff69d 100644
--- a/sync/internal_api/sync_manager_factory.cc
+++ b/sync/internal_api/sync_manager_factory.cc
@@ -4,32 +4,18 @@
 
 #include "sync/internal_api/public/sync_manager_factory.h"
 
-#include "sync/internal_api/sync_backup_manager.h"
 #include "sync/internal_api/sync_manager_impl.h"
-#include "sync/internal_api/sync_rollback_manager.h"
 
 namespace syncer {
 
-SyncManagerFactory::SyncManagerFactory(SyncManagerFactory::MANAGER_TYPE type)
-    : type_(type) {
-}
+SyncManagerFactory::SyncManagerFactory() {}
 
 SyncManagerFactory::~SyncManagerFactory() {
 }
 
 scoped_ptr<SyncManager> SyncManagerFactory::CreateSyncManager(
     const std::string& name) {
-  switch (type_) {
-    case NORMAL:
-      return scoped_ptr<SyncManager>(new SyncManagerImpl(name));
-    case BACKUP:
-      return scoped_ptr<SyncManager>(new SyncBackupManager());
-    case ROLLBACK:
-      return scoped_ptr<SyncManager>(new SyncRollbackManager());
-    default:
-      NOTREACHED();
-      return scoped_ptr<SyncManager>(new SyncManagerImpl(name));
-  }
+  return scoped_ptr<SyncManager>(new SyncManagerImpl(name));
 }
 
 }  // namespace syncer
diff --git a/sync/internal_api/sync_rollback_manager.cc b/sync/internal_api/sync_rollback_manager.cc
deleted file mode 100644
index e2a5c84..0000000
--- a/sync/internal_api/sync_rollback_manager.cc
+++ /dev/null
@@ -1,128 +0,0 @@
-// Copyright 2014 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/internal_api/sync_rollback_manager.h"
-
-#include <stddef.h>
-#include <stdint.h>
-
-#include "sync/internal_api/public/base/model_type.h"
-#include "sync/internal_api/public/read_node.h"
-#include "sync/internal_api/public/read_transaction.h"
-#include "sync/internal_api/public/util/syncer_error.h"
-#include "sync/internal_api/public/write_transaction.h"
-#include "sync/syncable/directory.h"
-#include "sync/syncable/mutable_entry.h"
-#include "url/gurl.h"
-
-namespace syncer {
-
-SyncRollbackManager::SyncRollbackManager()
-    : change_delegate_(NULL) {
-}
-
-SyncRollbackManager::~SyncRollbackManager() {
-}
-
-void SyncRollbackManager::Init(InitArgs* args) {
-  if (SyncRollbackManagerBase::InitInternal(
-          args->database_location,
-          args->internal_components_factory.get(),
-          InternalComponentsFactory::STORAGE_ON_DISK,
-          args->unrecoverable_error_handler,
-          args->report_unrecoverable_error_function)) {
-    change_delegate_ = args->change_delegate;
-
-    for (size_t i = 0; i < args->workers.size(); ++i) {
-      ModelSafeGroup group = args->workers[i]->GetModelSafeGroup();
-      CHECK(workers_.find(group) == workers_.end());
-      workers_[group] = args->workers[i];
-    }
-
-    rollback_ready_types_ = GetUserShare()->directory->InitialSyncEndedTypes();
-    rollback_ready_types_.RetainAll(BackupTypes());
-  }
-}
-
-void SyncRollbackManager::StartSyncingNormally(
-    const ModelSafeRoutingInfo& routing_info,
-    base::Time last_poll_time) {
-  if (rollback_ready_types_.Empty()) {
-    NotifyRollbackDone();
-    return;
-  }
-
-  std::map<ModelType, syncable::Directory::Metahandles> to_delete;
-  {
-    WriteTransaction trans(FROM_HERE, GetUserShare());
-    syncable::Directory::Metahandles unsynced;
-    GetUserShare()->directory->GetUnsyncedMetaHandles(trans.GetWrappedTrans(),
-                                                      &unsynced);
-    for (size_t i = 0; i < unsynced.size(); ++i) {
-      syncable::MutableEntry e(trans.GetWrappedWriteTrans(),
-                               syncable::GET_BY_HANDLE, unsynced[i]);
-      if (!e.good() || e.GetIsDel() || e.GetId().ServerKnows())
-        continue;
-
-      // TODO(haitaol): roll back entries that are backed up but whose content
-      //                is merged with local model during association.
-
-      ModelType type = GetModelTypeFromSpecifics(e.GetSpecifics());
-      if (!rollback_ready_types_.Has(type))
-        continue;
-
-      to_delete[type].push_back(unsynced[i]);
-    }
-  }
-
-  for (std::map<ModelType, syncable::Directory::Metahandles>::iterator it =
-      to_delete.begin(); it != to_delete.end(); ++it) {
-    ModelSafeGroup group = routing_info.find(it->first)->second;
-    CHECK(workers_.find(group) != workers_.end());
-    workers_[group]->DoWorkAndWaitUntilDone(
-        base::Bind(&SyncRollbackManager::DeleteOnWorkerThread,
-                   base::Unretained(this),
-                   it->first, it->second));
-  }
-
-  NotifyRollbackDone();
-}
-
-SyncerError SyncRollbackManager::DeleteOnWorkerThread(
-    ModelType type,
-    std::vector<int64_t> handles) {
-  CHECK(change_delegate_);
-
-  {
-    ChangeRecordList deletes;
-    WriteTransaction trans(FROM_HERE, GetUserShare());
-    for (size_t i = 0; i < handles.size(); ++i) {
-      syncable::MutableEntry e(trans.GetWrappedWriteTrans(),
-                               syncable::GET_BY_HANDLE, handles[i]);
-      if (!e.good() || e.GetIsDel())
-        continue;
-
-      ChangeRecord del;
-      del.action = ChangeRecord::ACTION_DELETE;
-      del.id = handles[i];
-      del.specifics = e.GetSpecifics();
-      deletes.push_back(del);
-    }
-
-    change_delegate_->OnChangesApplied(type, 1, &trans,
-                                       MakeImmutable(&deletes));
-  }
-
-  change_delegate_->OnChangesComplete(type);
-  return SYNCER_OK;
-}
-
-void SyncRollbackManager::NotifyRollbackDone() {
-  SyncProtocolError error;
-  error.action = ROLLBACK_DONE;
-  FOR_EACH_OBSERVER(SyncManager::Observer, *GetObservers(),
-                    OnActionableError(error));
-}
-
-}  // namespace syncer
diff --git a/sync/internal_api/sync_rollback_manager.h b/sync/internal_api/sync_rollback_manager.h
deleted file mode 100644
index d41086a..0000000
--- a/sync/internal_api/sync_rollback_manager.h
+++ /dev/null
@@ -1,52 +0,0 @@
-// Copyright 2014 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.
-
-#ifndef SYNC_INTERNAL_API_SYNC_ROLLBACK_MANAGER_H_
-#define SYNC_INTERNAL_API_SYNC_ROLLBACK_MANAGER_H_
-
-#include <stdint.h>
-
-#include <map>
-#include <string>
-#include <vector>
-
-#include "base/macros.h"
-#include "sync/internal_api/sync_rollback_manager_base.h"
-
-class GURL;
-
-namespace syncer {
-
-// SyncRollbackManager restores user's data to pre-sync state using backup
-// DB created by SyncBackupManager.
-class SYNC_EXPORT SyncRollbackManager : public SyncRollbackManagerBase {
- public:
-  SyncRollbackManager();
-  ~SyncRollbackManager() override;
-
-  // SyncManager implementation.
-  void Init(InitArgs* args) override;
-  void StartSyncingNormally(const ModelSafeRoutingInfo& routing_info,
-                            base::Time last_poll_time) override;
-
- private:
-  // Deletes specified entries in local model.
-  SyncerError DeleteOnWorkerThread(ModelType type,
-                                   std::vector<int64_t> handles);
-
-  void NotifyRollbackDone();
-
-  std::map<ModelSafeGroup, scoped_refptr<ModelSafeWorker> > workers_;
-
-  SyncManager::ChangeDelegate* change_delegate_;
-
-  // Types that can be rolled back.
-  ModelTypeSet rollback_ready_types_;
-
-  DISALLOW_COPY_AND_ASSIGN(SyncRollbackManager);
-};
-
-}  // namespace syncer
-
-#endif  // SYNC_INTERNAL_API_SYNC_ROLLBACK_MANAGER_H_
diff --git a/sync/internal_api/sync_rollback_manager_base.cc b/sync/internal_api/sync_rollback_manager_base.cc
deleted file mode 100644
index d62f354..0000000
--- a/sync/internal_api/sync_rollback_manager_base.cc
+++ /dev/null
@@ -1,329 +0,0 @@
-// Copyright 2014 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/internal_api/sync_rollback_manager_base.h"
-
-#include <stdint.h>
-
-#include "sync/internal_api/public/base/model_type.h"
-#include "sync/internal_api/public/read_node.h"
-#include "sync/internal_api/public/read_transaction.h"
-#include "sync/internal_api/public/write_transaction.h"
-#include "sync/syncable/directory_backing_store.h"
-#include "sync/syncable/mutable_entry.h"
-
-namespace {
-
-// Permanent bookmark folders as defined in bookmark_model_associator.cc.
-// No mobile bookmarks because they only exists with sync enabled.
-const char kBookmarkBarTag[] = "bookmark_bar";
-const char kOtherBookmarksTag[] = "other_bookmarks";
-
-class DummyEntryptionHandler : public syncer::SyncEncryptionHandler {
-  void AddObserver(Observer* observer) override {}
-  void RemoveObserver(Observer* observer) override {}
-  void Init() override {}
-  void SetEncryptionPassphrase(const std::string& passphrase,
-                               bool is_explicit) override {}
-  void SetDecryptionPassphrase(const std::string& passphrase) override {}
-  void EnableEncryptEverything() override {}
-  bool IsEncryptEverythingEnabled() const override { return false; }
-  syncer::PassphraseType GetPassphraseType() const override {
-    return syncer::KEYSTORE_PASSPHRASE;
-  }
-};
-
-}  // anonymous namespace
-
-namespace syncer {
-
-SyncRollbackManagerBase::SyncRollbackManagerBase()
-    : dummy_handler_(new DummyEntryptionHandler),
-      initialized_(false),
-      weak_ptr_factory_(this) {
-}
-
-SyncRollbackManagerBase::~SyncRollbackManagerBase() {
-}
-
-bool SyncRollbackManagerBase::InitInternal(
-    const base::FilePath& database_location,
-    InternalComponentsFactory* internal_components_factory,
-    InternalComponentsFactory::StorageOption storage,
-    const WeakHandle<UnrecoverableErrorHandler>& unrecoverable_error_handler,
-    const base::Closure& report_unrecoverable_error_function) {
-  unrecoverable_error_handler_ = unrecoverable_error_handler;
-  report_unrecoverable_error_function_ = report_unrecoverable_error_function;
-
-  if (!InitBackupDB(database_location, internal_components_factory, storage)) {
-    NotifyInitializationFailure();
-    return false;
-  }
-
-  initialized_ = true;
-  NotifyInitializationSuccess();
-  return true;
-}
-
-ModelTypeSet SyncRollbackManagerBase::InitialSyncEndedTypes() {
-  return share_.directory->InitialSyncEndedTypes();
-}
-
-ModelTypeSet SyncRollbackManagerBase::GetTypesWithEmptyProgressMarkerToken(
-      ModelTypeSet types) {
-  ModelTypeSet inited_types = share_.directory->InitialSyncEndedTypes();
-  types.RemoveAll(inited_types);
-  return types;
-}
-
-bool SyncRollbackManagerBase::PurgePartiallySyncedTypes() {
-  NOTREACHED();
-  return true;
-}
-
-void SyncRollbackManagerBase::UpdateCredentials(
-    const SyncCredentials& credentials) {
-}
-
-void SyncRollbackManagerBase::StartSyncingNormally(
-    const ModelSafeRoutingInfo& routing_info,
-    base::Time last_poll_time) {}
-
-void SyncRollbackManagerBase::ConfigureSyncer(
-      ConfigureReason reason,
-      ModelTypeSet to_download,
-      ModelTypeSet to_purge,
-      ModelTypeSet to_journal,
-      ModelTypeSet to_unapply,
-      const ModelSafeRoutingInfo& new_routing_info,
-      const base::Closure& ready_task,
-      const base::Closure& retry_task) {
-  for (ModelTypeSet::Iterator type = to_download.First();
-      type.Good(); type.Inc()) {
-    if (InitTypeRootNode(type.Get())) {
-      if (type.Get() == BOOKMARKS) {
-        InitBookmarkFolder(kBookmarkBarTag);
-        InitBookmarkFolder(kOtherBookmarksTag);
-      }
-    }
-  }
-
-  ready_task.Run();
-}
-
-void SyncRollbackManagerBase::SetInvalidatorEnabled(bool invalidator_enabled) {
-}
-
-void SyncRollbackManagerBase::OnIncomingInvalidation(
-    syncer::ModelType type,
-    scoped_ptr<InvalidationInterface> invalidation) {
-  NOTREACHED();
-}
-
-void SyncRollbackManagerBase::AddObserver(SyncManager::Observer* observer) {
-  observers_.AddObserver(observer);
-}
-
-void SyncRollbackManagerBase::RemoveObserver(SyncManager::Observer* observer) {
-  observers_.RemoveObserver(observer);
-}
-
-SyncStatus SyncRollbackManagerBase::GetDetailedStatus() const {
-  return SyncStatus();
-}
-
-void SyncRollbackManagerBase::SaveChanges() {
-}
-
-void SyncRollbackManagerBase::ShutdownOnSyncThread(ShutdownReason reason) {
-  if (initialized_) {
-    share_.directory.reset();
-    initialized_ = false;
-  }
-}
-
-UserShare* SyncRollbackManagerBase::GetUserShare() {
-  return &share_;
-}
-
-const std::string SyncRollbackManagerBase::cache_guid() {
-  return share_.directory->cache_guid();
-}
-
-bool SyncRollbackManagerBase::ReceivedExperiment(Experiments* experiments) {
-  return false;
-}
-
-bool SyncRollbackManagerBase::HasUnsyncedItems() {
-  ReadTransaction trans(FROM_HERE, &share_);
-  syncable::Directory::Metahandles unsynced;
-  share_.directory->GetUnsyncedMetaHandles(trans.GetWrappedTrans(), &unsynced);
-  return !unsynced.empty();
-}
-
-SyncEncryptionHandler* SyncRollbackManagerBase::GetEncryptionHandler() {
-  return dummy_handler_.get();
-}
-
-void SyncRollbackManagerBase::RefreshTypes(ModelTypeSet types) {
-}
-
-void SyncRollbackManagerBase::HandleTransactionCompleteChangeEvent(
-    ModelTypeSet models_with_changes) {
-}
-
-ModelTypeSet SyncRollbackManagerBase::HandleTransactionEndingChangeEvent(
-      const syncable::ImmutableWriteTransactionInfo& write_transaction_info,
-      syncable::BaseTransaction* trans) {
-  return ModelTypeSet();
-}
-
-void SyncRollbackManagerBase::HandleCalculateChangesChangeEventFromSyncApi(
-    const syncable::ImmutableWriteTransactionInfo& write_transaction_info,
-    syncable::BaseTransaction* trans,
-    std::vector<int64_t>* entries_changed) {}
-
-void SyncRollbackManagerBase::HandleCalculateChangesChangeEventFromSyncer(
-    const syncable::ImmutableWriteTransactionInfo& write_transaction_info,
-    syncable::BaseTransaction* trans,
-    std::vector<int64_t>* entries_changed) {}
-
-void SyncRollbackManagerBase::OnTransactionWrite(
-    const syncable::ImmutableWriteTransactionInfo& write_transaction_info,
-    ModelTypeSet models_with_changes) {
-}
-
-void SyncRollbackManagerBase::NotifyInitializationSuccess() {
-  FOR_EACH_OBSERVER(
-      SyncManager::Observer, observers_,
-      OnInitializationComplete(
-          MakeWeakHandle(base::WeakPtr<JsBackend>()),
-          MakeWeakHandle(base::WeakPtr<DataTypeDebugInfoListener>()),
-          true, InitialSyncEndedTypes()));
-}
-
-void SyncRollbackManagerBase::NotifyInitializationFailure() {
-  FOR_EACH_OBSERVER(
-      SyncManager::Observer, observers_,
-      OnInitializationComplete(
-          MakeWeakHandle(base::WeakPtr<JsBackend>()),
-          MakeWeakHandle(base::WeakPtr<DataTypeDebugInfoListener>()),
-          false, ModelTypeSet()));
-}
-
-syncer_v2::SyncContextProxy* SyncRollbackManagerBase::GetSyncContextProxy() {
-  return NULL;
-}
-
-ScopedVector<syncer::ProtocolEvent>
-SyncRollbackManagerBase::GetBufferedProtocolEvents() {
-  return ScopedVector<syncer::ProtocolEvent>();
-}
-
-scoped_ptr<base::ListValue> SyncRollbackManagerBase::GetAllNodesForType(
-    syncer::ModelType type) {
-  ReadTransaction trans(FROM_HERE, GetUserShare());
-  scoped_ptr<base::ListValue> nodes(
-      trans.GetDirectory()->GetNodeDetailsForType(trans.GetWrappedTrans(),
-                                                  type));
-  return nodes;
-}
-
-bool SyncRollbackManagerBase::InitBackupDB(
-    const base::FilePath& sync_folder,
-    InternalComponentsFactory* internal_components_factory,
-    InternalComponentsFactory::StorageOption storage) {
-  base::FilePath backup_db_path = sync_folder.Append(
-      syncable::Directory::kSyncDatabaseFilename);
-  scoped_ptr<syncable::DirectoryBackingStore> backing_store =
-      internal_components_factory->BuildDirectoryBackingStore(storage, "backup",
-                                                              backup_db_path);
-
-  DCHECK(backing_store.get());
-  share_.directory.reset(
-      new syncable::Directory(
-          backing_store.release(),
-          unrecoverable_error_handler_,
-          report_unrecoverable_error_function_,
-          NULL,
-          NULL));
-  return syncable::OPENED ==
-      share_.directory->Open(
-          "backup", this,
-          MakeWeakHandle(weak_ptr_factory_.GetWeakPtr()));
-}
-
-bool SyncRollbackManagerBase::InitTypeRootNode(ModelType type) {
-  WriteTransaction trans(FROM_HERE, &share_);
-  ReadNode root(&trans);
-  if (BaseNode::INIT_OK == root.InitTypeRoot(type))
-    return true;
-
-  syncable::MutableEntry entry(trans.GetWrappedWriteTrans(),
-                               syncable::CREATE_NEW_UPDATE_ITEM,
-                               syncable::Id::CreateFromServerId(
-                                   ModelTypeToString(type)));
-  if (!entry.good())
-    return false;
-
-  entry.PutParentId(syncable::Id::GetRoot());
-  entry.PutBaseVersion(1);
-  entry.PutUniqueServerTag(ModelTypeToRootTag(type));
-  entry.PutNonUniqueName(ModelTypeToString(type));
-  entry.PutIsDel(false);
-  entry.PutIsDir(true);
-
-  sync_pb::EntitySpecifics specifics;
-  AddDefaultFieldValue(type, &specifics);
-  entry.PutSpecifics(specifics);
-
-  return true;
-}
-
-void SyncRollbackManagerBase::InitBookmarkFolder(const std::string& folder) {
-  WriteTransaction trans(FROM_HERE, &share_);
-  syncable::Entry bookmark_root(trans.GetWrappedTrans(),
-                                syncable::GET_TYPE_ROOT,
-                                BOOKMARKS);
-  if (!bookmark_root.good())
-    return;
-
-  syncable::MutableEntry entry(trans.GetWrappedWriteTrans(),
-                               syncable::CREATE_NEW_UPDATE_ITEM,
-                               syncable::Id::CreateFromServerId(folder));
-  if (!entry.good())
-    return;
-
-  entry.PutParentId(bookmark_root.GetId());
-  entry.PutBaseVersion(1);
-  entry.PutUniqueServerTag(folder);
-  entry.PutNonUniqueName(folder);
-  entry.PutIsDel(false);
-  entry.PutIsDir(true);
-
-  sync_pb::EntitySpecifics specifics;
-  AddDefaultFieldValue(BOOKMARKS, &specifics);
-  entry.PutSpecifics(specifics);
-}
-
-base::ObserverList<SyncManager::Observer>*
-SyncRollbackManagerBase::GetObservers() {
-  return &observers_;
-}
-
-void SyncRollbackManagerBase::RegisterDirectoryTypeDebugInfoObserver(
-    syncer::TypeDebugInfoObserver* observer) {}
-
-void SyncRollbackManagerBase::UnregisterDirectoryTypeDebugInfoObserver(
-    syncer::TypeDebugInfoObserver* observer) {}
-
-bool SyncRollbackManagerBase::HasDirectoryTypeDebugInfoObserver(
-    syncer::TypeDebugInfoObserver* observer) { return false; }
-
-void SyncRollbackManagerBase::RequestEmitDebugInfo() {}
-
-void SyncRollbackManagerBase::ClearServerData(
-    const ClearServerDataCallback& callback) {}
-
-}  // namespace syncer
diff --git a/sync/internal_api/sync_rollback_manager_base.h b/sync/internal_api/sync_rollback_manager_base.h
deleted file mode 100644
index ad3ad62..0000000
--- a/sync/internal_api/sync_rollback_manager_base.h
+++ /dev/null
@@ -1,149 +0,0 @@
-// Copyright 2014 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.
-
-#ifndef SYNC_INTERNAL_API_SYNC_ROLLBACK_MANAGER_BASE_H_
-#define SYNC_INTERNAL_API_SYNC_ROLLBACK_MANAGER_BASE_H_
-
-#include <stdint.h>
-
-#include <string>
-#include <vector>
-
-#include "base/macros.h"
-#include "sync/base/sync_export.h"
-#include "sync/internal_api/public/http_post_provider_factory.h"
-#include "sync/internal_api/public/internal_components_factory.h"
-#include "sync/internal_api/public/sync_manager.h"
-#include "sync/internal_api/public/user_share.h"
-#include "sync/syncable/directory_change_delegate.h"
-#include "sync/syncable/transaction_observer.h"
-
-namespace syncer {
-
-class WriteTransaction;
-
-// Base class of sync managers used for backup and rollback. Two major
-// functions are:
-//   * Init(): load backup DB into sync directory.
-//   * ConfigureSyncer(): initialize permanent sync nodes (root, bookmark
-//                        permanent folders) for configured type as needed.
-//
-// Most of other functions are no ops.
-class SYNC_EXPORT SyncRollbackManagerBase
-    : public SyncManager,
-      public syncable::DirectoryChangeDelegate,
-      public syncable::TransactionObserver {
- public:
-  SyncRollbackManagerBase();
-  ~SyncRollbackManagerBase() override;
-
-  // SyncManager implementation.
-  ModelTypeSet InitialSyncEndedTypes() override;
-  ModelTypeSet GetTypesWithEmptyProgressMarkerToken(
-      ModelTypeSet types) override;
-  bool PurgePartiallySyncedTypes() override;
-  void UpdateCredentials(const SyncCredentials& credentials) override;
-  void StartSyncingNormally(const ModelSafeRoutingInfo& routing_info,
-                            base::Time last_poll_time) override;
-  void ConfigureSyncer(ConfigureReason reason,
-                       ModelTypeSet to_download,
-                       ModelTypeSet to_purge,
-                       ModelTypeSet to_journal,
-                       ModelTypeSet to_unapply,
-                       const ModelSafeRoutingInfo& new_routing_info,
-                       const base::Closure& ready_task,
-                       const base::Closure& retry_task) override;
-  void SetInvalidatorEnabled(bool invalidator_enabled) override;
-  void OnIncomingInvalidation(
-      syncer::ModelType type,
-      scoped_ptr<InvalidationInterface> invalidation) override;
-  void AddObserver(SyncManager::Observer* observer) override;
-  void RemoveObserver(SyncManager::Observer* observer) override;
-  SyncStatus GetDetailedStatus() const override;
-  void SaveChanges() override;
-  void ShutdownOnSyncThread(ShutdownReason reason) override;
-  UserShare* GetUserShare() override;
-  const std::string cache_guid() override;
-  bool ReceivedExperiment(Experiments* experiments) override;
-  bool HasUnsyncedItems() override;
-  SyncEncryptionHandler* GetEncryptionHandler() override;
-  void RefreshTypes(ModelTypeSet types) override;
-  syncer_v2::SyncContextProxy* GetSyncContextProxy() override;
-  ScopedVector<ProtocolEvent> GetBufferedProtocolEvents() override;
-  scoped_ptr<base::ListValue> GetAllNodesForType(
-      syncer::ModelType type) override;
-  void ClearServerData(const ClearServerDataCallback& callback) override;
-
-  // DirectoryChangeDelegate implementation.
-  void HandleTransactionCompleteChangeEvent(
-      ModelTypeSet models_with_changes) override;
-  ModelTypeSet HandleTransactionEndingChangeEvent(
-      const syncable::ImmutableWriteTransactionInfo& write_transaction_info,
-      syncable::BaseTransaction* trans) override;
-  void HandleCalculateChangesChangeEventFromSyncApi(
-      const syncable::ImmutableWriteTransactionInfo& write_transaction_info,
-      syncable::BaseTransaction* trans,
-      std::vector<int64_t>* entries_changed) override;
-  void HandleCalculateChangesChangeEventFromSyncer(
-      const syncable::ImmutableWriteTransactionInfo& write_transaction_info,
-      syncable::BaseTransaction* trans,
-      std::vector<int64_t>* entries_changed) override;
-
-  // syncable::TransactionObserver implementation.
-  void OnTransactionWrite(
-      const syncable::ImmutableWriteTransactionInfo& write_transaction_info,
-      ModelTypeSet models_with_changes) override;
-
- protected:
-  base::ObserverList<SyncManager::Observer>* GetObservers();
-
-  // Initialize sync backup DB.
-  bool InitInternal(
-      const base::FilePath& database_location,
-      InternalComponentsFactory* internal_components_factory,
-      InternalComponentsFactory::StorageOption storage,
-      const WeakHandle<UnrecoverableErrorHandler>& unrecoverable_error_handler,
-      const base::Closure& report_unrecoverable_error_function);
-
-  void RegisterDirectoryTypeDebugInfoObserver(
-      syncer::TypeDebugInfoObserver* observer) override;
-  void UnregisterDirectoryTypeDebugInfoObserver(
-      syncer::TypeDebugInfoObserver* observer) override;
-  bool HasDirectoryTypeDebugInfoObserver(
-      syncer::TypeDebugInfoObserver* observer) override;
-  void RequestEmitDebugInfo() override;
-
-  bool initialized() const {
-    return initialized_;
-  }
-
- private:
-  void NotifyInitializationSuccess();
-  void NotifyInitializationFailure();
-
-  bool InitBackupDB(const base::FilePath& sync_folder,
-                    InternalComponentsFactory* internal_components_factory,
-                    InternalComponentsFactory::StorageOption storage);
-
-  bool InitTypeRootNode(ModelType type);
-  void InitBookmarkFolder(const std::string& folder);
-
-  UserShare share_;
-  base::ObserverList<SyncManager::Observer> observers_;
-
-  WeakHandle<UnrecoverableErrorHandler> unrecoverable_error_handler_;
-  base::Closure report_unrecoverable_error_function_;
-
-  scoped_ptr<SyncEncryptionHandler> dummy_handler_;
-
-  bool initialized_;
-
-  base::WeakPtrFactory<SyncRollbackManagerBase> weak_ptr_factory_;
-
-  DISALLOW_COPY_AND_ASSIGN(SyncRollbackManagerBase);
-};
-
-}  // namespace syncer
-
-#endif  // SYNC_INTERNAL_API_SYNC_ROLLBACK_MANAGER_BASE_H_
diff --git a/sync/internal_api/sync_rollback_manager_base_unittest.cc b/sync/internal_api/sync_rollback_manager_base_unittest.cc
deleted file mode 100644
index bb5ec93..0000000
--- a/sync/internal_api/sync_rollback_manager_base_unittest.cc
+++ /dev/null
@@ -1,84 +0,0 @@
-// Copyright 2014 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/internal_api/sync_rollback_manager_base.h"
-
-#include "base/bind.h"
-#include "sync/internal_api/public/read_node.h"
-#include "sync/internal_api/public/read_transaction.h"
-#include "sync/internal_api/public/test/test_internal_components_factory.h"
-#include "testing/gtest/include/gtest/gtest.h"
-#include "url/gurl.h"
-
-namespace syncer {
-
-namespace {
-
-void OnConfigDone(bool success) {
-  EXPECT_TRUE(success);
-}
-
-class SyncTestRollbackManager : public SyncRollbackManagerBase {
- public:
-  void Init(InitArgs* args) override {
-    SyncRollbackManagerBase::InitInternal(
-        args->database_location,
-        args->internal_components_factory.get(),
-        InternalComponentsFactory::STORAGE_IN_MEMORY,
-        args->unrecoverable_error_handler,
-        args->report_unrecoverable_error_function);
-  }
-};
-
-class SyncRollbackManagerBaseTest : public testing::Test {
- protected:
-  void SetUp() override {
-    SyncManager::InitArgs args;
-    args.database_location = base::FilePath(base::FilePath::kCurrentDirectory);
-    args.service_url = GURL("https://example.com/");
-    args.internal_components_factory.reset(new TestInternalComponentsFactory(
-        InternalComponentsFactory::Switches(),
-        InternalComponentsFactory::STORAGE_IN_MEMORY,
-        &storage_used_));
-    manager_.Init(&args);
-    EXPECT_EQ(InternalComponentsFactory::STORAGE_IN_MEMORY, storage_used_);
-  }
-
-  SyncTestRollbackManager manager_;
-  base::MessageLoop loop_;    // Needed for WeakHandle
-  InternalComponentsFactory::StorageOption storage_used_;
-};
-
-TEST_F(SyncRollbackManagerBaseTest, InitTypeOnConfiguration) {
-  EXPECT_TRUE(manager_.InitialSyncEndedTypes().Empty());
-
-  manager_.ConfigureSyncer(
-      CONFIGURE_REASON_NEW_CLIENT,
-      ModelTypeSet(PREFERENCES, BOOKMARKS),
-      ModelTypeSet(), ModelTypeSet(), ModelTypeSet(), ModelSafeRoutingInfo(),
-      base::Bind(&OnConfigDone, true),
-      base::Bind(&OnConfigDone, false));
-
-  ReadTransaction trans(FROM_HERE, manager_.GetUserShare());
-  ReadNode pref_root(&trans);
-  EXPECT_EQ(BaseNode::INIT_OK,
-            pref_root.InitTypeRoot(PREFERENCES));
-
-  ReadNode bookmark_root(&trans);
-  EXPECT_EQ(BaseNode::INIT_OK,
-            bookmark_root.InitTypeRoot(BOOKMARKS));
-  ReadNode bookmark_bar(&trans);
-  EXPECT_EQ(BaseNode::INIT_OK,
-            bookmark_bar.InitByTagLookupForBookmarks("bookmark_bar"));
-  ReadNode bookmark_mobile(&trans);
-  EXPECT_EQ(BaseNode::INIT_FAILED_ENTRY_NOT_GOOD,
-            bookmark_mobile.InitByTagLookupForBookmarks("synced_bookmarks"));
-  ReadNode bookmark_other(&trans);
-  EXPECT_EQ(BaseNode::INIT_OK,
-            bookmark_other.InitByTagLookupForBookmarks("other_bookmarks"));
-}
-
-}  // anonymous namespace
-
-}  // namespace syncer
diff --git a/sync/internal_api/sync_rollback_manager_unittest.cc b/sync/internal_api/sync_rollback_manager_unittest.cc
deleted file mode 100644
index 400cebc..0000000
--- a/sync/internal_api/sync_rollback_manager_unittest.cc
+++ /dev/null
@@ -1,269 +0,0 @@
-// Copyright 2014 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/internal_api/sync_rollback_manager.h"
-
-#include <stddef.h>
-#include <stdint.h>
-
-#include <set>
-
-#include "base/files/scoped_temp_dir.h"
-#include "base/run_loop.h"
-#include "sync/internal_api/public/read_node.h"
-#include "sync/internal_api/public/read_transaction.h"
-#include "sync/internal_api/public/sessions/sync_session_snapshot.h"
-#include "sync/internal_api/public/test/test_internal_components_factory.h"
-#include "sync/internal_api/public/write_node.h"
-#include "sync/internal_api/public/write_transaction.h"
-#include "sync/internal_api/sync_backup_manager.h"
-#include "sync/syncable/entry.h"
-#include "sync/test/engine/fake_model_worker.h"
-#include "sync/test/test_directory_backing_store.h"
-#include "testing/gmock/include/gmock/gmock.h"
-#include "testing/gtest/include/gtest/gtest.h"
-#include "url/gurl.h"
-
-using ::testing::_;
-using ::testing::DoDefault;
-using ::testing::Invoke;
-using ::testing::Truly;
-using ::testing::WithArgs;
-
-namespace syncer {
-
-namespace {
-
-class TestChangeDelegate : public SyncManager::ChangeDelegate {
- public:
-  TestChangeDelegate() {
-    ON_CALL(*this, OnChangesApplied(_, _, _, _))
-        .WillByDefault(
-            WithArgs<3>(Invoke(this,
-                               &TestChangeDelegate::VerifyDeletes)));
-  }
-
-  void add_expected_delete(int64_t v) { expected_deletes_.insert(v); }
-
-  MOCK_METHOD4(OnChangesApplied,
-               void(ModelType model_type,
-                    int64_t model_version,
-                    const BaseTransaction* trans,
-                    const ImmutableChangeRecordList& changes));
-  MOCK_METHOD1(OnChangesComplete, void(ModelType model_type));
-
- private:
-  void VerifyDeletes(const ImmutableChangeRecordList& changes) {
-    std::set<int64_t> deleted;
-    for (size_t i = 0; i < changes.Get().size(); ++i) {
-      const ChangeRecord& change = (changes.Get())[i];
-      EXPECT_EQ(ChangeRecord::ACTION_DELETE, change.action);
-      EXPECT_TRUE(deleted.find(change.id) == deleted.end());
-      deleted.insert(change.id);
-    }
-    EXPECT_TRUE(expected_deletes_ == deleted);
-  }
-
-  std::set<int64_t> expected_deletes_;
-};
-
-class SyncRollbackManagerTest : public testing::Test,
-                                public SyncManager::Observer {
- protected:
-  void SetUp() override {
-    CHECK(temp_dir_.CreateUniqueTempDir());
-
-    worker_ = new FakeModelWorker(GROUP_UI);
-  }
-
-  MOCK_METHOD1(OnSyncCycleCompleted,
-               void(const sessions::SyncSessionSnapshot&));
-  MOCK_METHOD1(OnConnectionStatusChange, void(ConnectionStatus));
-  MOCK_METHOD4(OnInitializationComplete,
-               void(const WeakHandle<JsBackend>&,
-                    const WeakHandle<DataTypeDebugInfoListener>&,
-                    bool, ModelTypeSet));
-  MOCK_METHOD1(OnActionableError, void(const SyncProtocolError&));
-  MOCK_METHOD1(OnMigrationRequested, void(ModelTypeSet));
-  MOCK_METHOD1(OnProtocolEvent, void(const ProtocolEvent&));
-
-  void OnConfigDone(bool success) {
-    EXPECT_TRUE(success);
-  }
-
-  int64_t CreateEntry(UserShare* user_share,
-                      ModelType type,
-                      const std::string& client_tag) {
-    WriteTransaction trans(FROM_HERE, user_share);
-    WriteNode node(&trans);
-    EXPECT_EQ(WriteNode::INIT_SUCCESS,
-              node.InitUniqueByCreation(type, client_tag));
-    return node.GetId();
-  }
-
-  void InitManager(SyncManager* manager, ModelTypeSet types,
-                   TestChangeDelegate* delegate,
-                   InternalComponentsFactory::StorageOption storage_option) {
-    manager_ = manager;
-    types_ = types;
-
-    EXPECT_CALL(*this, OnInitializationComplete(_, _, _, _))
-        .WillOnce(WithArgs<2>(Invoke(this,
-                                     &SyncRollbackManagerTest::HandleInit)));
-
-    manager->AddObserver(this);
-
-    base::RunLoop run_loop;
-    SyncManager::InitArgs args;
-    args.database_location = temp_dir_.path();
-    args.service_url = GURL("https://example.com/");
-    args.workers.push_back(worker_);
-    args.change_delegate = delegate;
-
-    InternalComponentsFactory::StorageOption storage_used;
-    args.internal_components_factory.reset(new TestInternalComponentsFactory(
-        InternalComponentsFactory::Switches(), storage_option, &storage_used));
-    manager->Init(&args);
-    EXPECT_EQ(storage_option, storage_used);
-    loop_.PostTask(FROM_HERE, run_loop.QuitClosure());
-    run_loop.Run();
-  }
-
-  // Create and persist an entry by unique tag in DB.
-  void PrepopulateDb(ModelType type, const std::string& client_tag) {
-    SyncBackupManager backup_manager;
-    TestChangeDelegate delegate;
-    InitManager(&backup_manager, ModelTypeSet(type), &delegate,
-                InternalComponentsFactory::STORAGE_ON_DISK_DEFERRED);
-    CreateEntry(backup_manager.GetUserShare(), type, client_tag);
-    backup_manager.ShutdownOnSyncThread(SWITCH_MODE_SYNC);
-  }
-
-  // Verify entry with |client_tag| exists in sync directory.
-  bool VerifyEntry(UserShare* user_share, ModelType type,
-                   const std::string& client_tag) {
-    ReadTransaction trans(FROM_HERE, user_share);
-    ReadNode node(&trans);
-    return BaseNode::INIT_OK == node.InitByClientTagLookup(type, client_tag);
-  }
-
- private:
-  void ConfigureSyncer() {
-    manager_->ConfigureSyncer(
-          CONFIGURE_REASON_NEW_CLIENT,
-          types_,
-          ModelTypeSet(), ModelTypeSet(), ModelTypeSet(),
-          ModelSafeRoutingInfo(),
-          base::Bind(&SyncRollbackManagerTest::OnConfigDone,
-                     base::Unretained(this), true),
-          base::Bind(&SyncRollbackManagerTest::OnConfigDone,
-                     base::Unretained(this), false));
-  }
-
-  void HandleInit(bool success) {
-    if (success) {
-      loop_.PostTask(FROM_HERE,
-                     base::Bind(&SyncRollbackManagerTest::ConfigureSyncer,
-                                base::Unretained(this)));
-    } else {
-      manager_->ShutdownOnSyncThread(STOP_SYNC);
-    }
-  }
-
-  base::ScopedTempDir temp_dir_;
-  scoped_refptr<ModelSafeWorker> worker_;
-  base::MessageLoop loop_;    // Needed for WeakHandle
-  SyncManager* manager_;
-  ModelTypeSet types_;
-};
-
-bool IsRollbackDoneAction(SyncProtocolError e) {
-  return e.action == syncer::ROLLBACK_DONE;
-}
-
-TEST_F(SyncRollbackManagerTest, RollbackBasic) {
-  PrepopulateDb(PREFERENCES, "pref1");
-
-  TestChangeDelegate delegate;
-  SyncRollbackManager rollback_manager;
-  InitManager(&rollback_manager, ModelTypeSet(PREFERENCES), &delegate,
-              InternalComponentsFactory::STORAGE_ON_DISK);
-
-  // Simulate a new entry added during type initialization.
-  int64_t new_pref_id =
-      CreateEntry(rollback_manager.GetUserShare(), PREFERENCES, "pref2");
-
-  delegate.add_expected_delete(new_pref_id);
-  EXPECT_CALL(delegate, OnChangesApplied(_, _, _, _))
-      .Times(1)
-      .WillOnce(DoDefault());
-  EXPECT_CALL(delegate, OnChangesComplete(_)).Times(1);
-  EXPECT_CALL(*this, OnActionableError(Truly(IsRollbackDoneAction))).Times(1);
-
-  ModelSafeRoutingInfo routing_info;
-  routing_info[PREFERENCES] = GROUP_UI;
-  rollback_manager.StartSyncingNormally(routing_info, base::Time());
-}
-
-TEST_F(SyncRollbackManagerTest, NoRollbackOfTypesNotBackedUp) {
-  PrepopulateDb(PREFERENCES, "pref1");
-
-  TestChangeDelegate delegate;
-  SyncRollbackManager rollback_manager;
-  InitManager(&rollback_manager, ModelTypeSet(PREFERENCES, APPS), &delegate,
-              InternalComponentsFactory::STORAGE_ON_DISK);
-
-  // Simulate new entry added during type initialization.
-  int64_t new_pref_id =
-      CreateEntry(rollback_manager.GetUserShare(), PREFERENCES, "pref2");
-  CreateEntry(rollback_manager.GetUserShare(), APPS, "app1");
-
-  delegate.add_expected_delete(new_pref_id);
-  EXPECT_CALL(delegate, OnChangesApplied(_, _, _, _))
-      .Times(1)
-      .WillOnce(DoDefault());
-  EXPECT_CALL(delegate, OnChangesComplete(_)).Times(1);
-
-  ModelSafeRoutingInfo routing_info;
-  routing_info[PREFERENCES] = GROUP_UI;
-  rollback_manager.StartSyncingNormally(routing_info, base::Time());
-
-  // APP entry is still valid.
-  EXPECT_TRUE(VerifyEntry(rollback_manager.GetUserShare(), APPS, "app1"));
-}
-
-TEST_F(SyncRollbackManagerTest, BackupDbNotChangedOnAbort) {
-  PrepopulateDb(PREFERENCES, "pref1");
-
-  TestChangeDelegate delegate;
-  scoped_ptr<SyncRollbackManager> rollback_manager(
-      new SyncRollbackManager);
-  InitManager(rollback_manager.get(), ModelTypeSet(PREFERENCES), &delegate,
-              InternalComponentsFactory::STORAGE_ON_DISK);
-
-  // Simulate a new entry added during type initialization.
-  CreateEntry(rollback_manager->GetUserShare(), PREFERENCES, "pref2");
-
-  // Manager was shut down before sync starts.
-  rollback_manager->ShutdownOnSyncThread(STOP_SYNC);
-
-  // Verify new entry was not persisted.
-  rollback_manager.reset(new SyncRollbackManager);
-  InitManager(rollback_manager.get(), ModelTypeSet(PREFERENCES), &delegate,
-              InternalComponentsFactory::STORAGE_ON_DISK);
-  EXPECT_FALSE(VerifyEntry(rollback_manager->GetUserShare(), PREFERENCES,
-                           "pref2"));
-}
-
-TEST_F(SyncRollbackManagerTest, OnInitializationFailure) {
-  // Test graceful shutdown on initialization failure.
-  scoped_ptr<SyncRollbackManager> rollback_manager(
-      new SyncRollbackManager);
-  InitManager(rollback_manager.get(), ModelTypeSet(PREFERENCES), NULL,
-              InternalComponentsFactory::STORAGE_ON_DISK);
-}
-
-}  // anonymous namespace
-
-}  // namespace syncer
diff --git a/sync/internal_api/test/sync_manager_factory_for_profile_sync_test.cc b/sync/internal_api/test/sync_manager_factory_for_profile_sync_test.cc
index ff72bcd..4c0689d 100644
--- a/sync/internal_api/test/sync_manager_factory_for_profile_sync_test.cc
+++ b/sync/internal_api/test/sync_manager_factory_for_profile_sync_test.cc
@@ -10,7 +10,7 @@ namespace syncer {
 
 SyncManagerFactoryForProfileSyncTest::SyncManagerFactoryForProfileSyncTest(
     base::Closure init_callback)
-  : SyncManagerFactory(SyncManagerFactory::NORMAL),
+  : SyncManagerFactory(),
     init_callback_(init_callback) {
 }
 
@@ -20,9 +20,7 @@ scoped_ptr<syncer::SyncManager>
 SyncManagerFactoryForProfileSyncTest::CreateSyncManager(
     const std::string& name) {
   return scoped_ptr<syncer::SyncManager>(
-      new SyncManagerForProfileSyncTest(
-          name,
-          init_callback_));
+      new SyncManagerForProfileSyncTest(name, init_callback_));
 }
 
 }  // namespace syncer
diff --git a/sync/internal_api/test/test_internal_components_factory.cc b/sync/internal_api/test/test_internal_components_factory.cc
index 1e26b4e..d6a72fa 100644
--- a/sync/internal_api/test/test_internal_components_factory.cc
+++ b/sync/internal_api/test/test_internal_components_factory.cc
@@ -5,7 +5,6 @@
 #include "sync/internal_api/public/test/test_internal_components_factory.h"
 
 #include "sync/sessions/sync_session_context.h"
-#include "sync/syncable/deferred_on_disk_directory_backing_store.h"
 #include "sync/syncable/in_memory_directory_backing_store.h"
 #include "sync/syncable/on_disk_directory_backing_store.h"
 #include "sync/syncable/invalid_directory_backing_store.h"
@@ -69,10 +68,6 @@ TestInternalComponentsFactory::BuildDirectoryBackingStore(
       return scoped_ptr<syncable::DirectoryBackingStore>(
           new syncable::OnDiskDirectoryBackingStore(dir_name,
                                                     backing_filepath));
-    case STORAGE_ON_DISK_DEFERRED:
-      return scoped_ptr<syncable::DirectoryBackingStore>(
-          new syncable::DeferredOnDiskDirectoryBackingStore(dir_name,
-                                                            backing_filepath));
     case STORAGE_INVALID:
       return scoped_ptr<syncable::DirectoryBackingStore>(
           new syncable::InvalidDirectoryBackingStore());
diff --git a/sync/protocol/device_info_specifics.proto b/sync/protocol/device_info_specifics.proto
index 99af88b..0103aa6 100644
--- a/sync/protocol/device_info_specifics.proto
+++ b/sync/protocol/device_info_specifics.proto
@@ -37,7 +37,8 @@ message DeviceInfoSpecifics {
 
   // Last time when pre-sync data on the device was saved. The device can be
   // restored to state back to this time. In millisecond since UNIX epoch.
-  optional int64 backup_timestamp = 6;
+  // DEPRECATED in M50.
+  optional int64 deprecated_backup_timestamp = 6 [deprecated=true];
 
   // Device_id that is stable until user signs out. This device_id is used for
   // annotating login scoped refresh token.
diff --git a/sync/protocol/proto_enum_conversions.cc b/sync/protocol/proto_enum_conversions.cc
index 0c6cf73..84a5b03 100644
--- a/sync/protocol/proto_enum_conversions.cc
+++ b/sync/protocol/proto_enum_conversions.cc
@@ -164,7 +164,7 @@ const char* GetErrorTypeString(sync_pb::SyncEnums::ErrorType error_type) {
     ENUM_CASE(sync_pb::SyncEnums, TRANSIENT_ERROR);
     ENUM_CASE(sync_pb::SyncEnums, MIGRATION_DONE);
     ENUM_CASE(sync_pb::SyncEnums, DISABLED_BY_ADMIN);
-    ENUM_CASE(sync_pb::SyncEnums, USER_ROLLBACK);
+    ENUM_CASE(sync_pb::SyncEnums, DEPRECATED_USER_ROLLBACK);
     ENUM_CASE(sync_pb::SyncEnums, PARTIAL_FAILURE);
     ENUM_CASE(sync_pb::SyncEnums, CLIENT_DATA_OBSOLETE);
     ENUM_CASE(sync_pb::SyncEnums, UNKNOWN);
diff --git a/sync/protocol/proto_value_conversions.cc b/sync/protocol/proto_value_conversions.cc
index 4fee4ee..327723c 100644
--- a/sync/protocol/proto_value_conversions.cc
+++ b/sync/protocol/proto_value_conversions.cc
@@ -80,10 +80,6 @@ scoped_ptr<base::ListValue> MakeRepeatedValue(const F& fields,
   return list;
 }
 
-base::string16 TimestampToString(int64_t tm) {
-  return base::TimeFormatShortDateAndTime(syncer::ProtoTimeToTime(tm));
-}
-
 }  // namespace
 
 // Helper macros to reduce the amount of boilerplate.
@@ -412,7 +408,6 @@ scoped_ptr<base::DictionaryValue> DeviceInfoSpecificsToValue(
   SET_ENUM(device_type, GetDeviceTypeString);
   SET_STR(sync_user_agent);
   SET_STR(chrome_version);
-  SET_TIME_STR(backup_timestamp);
   SET_STR(signin_scoped_device_id);
   return value;
 }
diff --git a/sync/protocol/sync_enums.proto b/sync/protocol/sync_enums.proto
index bdfb45e..0e18575 100644
--- a/sync/protocol/sync_enums.proto
+++ b/sync/protocol/sync_enums.proto
@@ -96,7 +96,7 @@ message SyncEnums {
                                 // a server.
     DISABLED_BY_ADMIN    = 10;  // An administrator disabled sync for this
                                 // domain.
-    USER_ROLLBACK        = 11;  // Client told to stop syncing and roll back.
+    DEPRECATED_USER_ROLLBACK        = 11;  // Deprecated in M50.
     PARTIAL_FAILURE      = 12;  // Return when client want to update several
                                 // data types, but some of them failed(e.g.
                                 // throttled).
diff --git a/sync/protocol/sync_protocol_error.cc b/sync/protocol/sync_protocol_error.cc
index 992f6ac..c82d32e 100644
--- a/sync/protocol/sync_protocol_error.cc
+++ b/sync/protocol/sync_protocol_error.cc
@@ -22,7 +22,6 @@ const char* GetSyncErrorTypeString(SyncProtocolErrorType type) {
     ENUM_CASE(MIGRATION_DONE);
     ENUM_CASE(INVALID_CREDENTIAL);
     ENUM_CASE(DISABLED_BY_ADMIN);
-    ENUM_CASE(USER_ROLLBACK);
     ENUM_CASE(PARTIAL_FAILURE);
     ENUM_CASE(CLIENT_DATA_OBSOLETE);
     ENUM_CASE(UNKNOWN_ERROR);
@@ -39,8 +38,6 @@ const char* GetClientActionString(ClientAction action) {
     ENUM_CASE(STOP_AND_RESTART_SYNC);
     ENUM_CASE(DISABLE_SYNC_ON_CLIENT);
     ENUM_CASE(STOP_SYNC_FOR_DISABLED_ACCOUNT);
-    ENUM_CASE(DISABLE_SYNC_AND_ROLLBACK);
-    ENUM_CASE(ROLLBACK_DONE);
     ENUM_CASE(RESET_LOCAL_SYNC_DATA);
     ENUM_CASE(UNKNOWN_ACTION);
   }
diff --git a/sync/protocol/sync_protocol_error.h b/sync/protocol/sync_protocol_error.h
index 38c5f18..7ba8d6c 100644
--- a/sync/protocol/sync_protocol_error.h
+++ b/sync/protocol/sync_protocol_error.h
@@ -38,9 +38,6 @@ enum SyncProtocolErrorType {
   // An administrator disabled sync for this domain.
   DISABLED_BY_ADMIN,
 
-  // Client told to stop syncing this device and roll back local data.
-  USER_ROLLBACK,
-
   // Some of servers are busy. Try later with busy servers.
   PARTIAL_FAILURE,
 
@@ -72,13 +69,6 @@ enum ClientAction {
   // settings page that account is disabled.
   STOP_SYNC_FOR_DISABLED_ACCOUNT,
 
-  // Disable sync and roll back local model to pre-sync state.
-  DISABLE_SYNC_AND_ROLLBACK,
-
-  // Generated by SyncRollbackManager to notify ProfileSyncService that
-  // rollback is finished.
-  ROLLBACK_DONE,
-
   // Generated in response to CLIENT_DATA_OBSOLETE error. ProfileSyncService
   // should stop sync engine, delete directory and restart sync engine.
   RESET_LOCAL_SYNC_DATA,
diff --git a/sync/sync.gyp b/sync/sync.gyp
index 9981376..f5303cb 100644
--- a/sync/sync.gyp
+++ b/sync/sync.gyp
@@ -350,8 +350,6 @@
         'internal_api/read_node.cc',
         'internal_api/read_transaction.cc',
         'internal_api/shared_model_type_processor.cc',
-        'internal_api/sync_backup_manager.cc',
-        'internal_api/sync_backup_manager.h',
         'internal_api/sync_context.cc',
         'internal_api/sync_context_proxy.cc',
         'internal_api/sync_context_proxy_impl.cc',
@@ -362,10 +360,6 @@
         'internal_api/sync_manager_factory.cc',
         'internal_api/sync_manager_impl.cc',
         'internal_api/sync_manager_impl.h',
-        'internal_api/sync_rollback_manager.cc',
-        'internal_api/sync_rollback_manager.h',
-        'internal_api/sync_rollback_manager_base.cc',
-        'internal_api/sync_rollback_manager_base.h',
         'internal_api/syncapi_internal.cc',
         'internal_api/syncapi_internal.h',
         'internal_api/syncapi_server_connection_manager.cc',
@@ -401,8 +395,6 @@
         'sessions/sync_session.h',
         'sessions/sync_session_context.cc',
         'sessions/sync_session_context.h',
-        'syncable/deferred_on_disk_directory_backing_store.cc',
-        'syncable/deferred_on_disk_directory_backing_store.h',
         'syncable/dir_open_result.h',
         'syncable/directory.cc',
         'syncable/directory.h',
diff --git a/sync/sync_tests.gypi b/sync/sync_tests.gypi
index 122641e..bacf837 100644
--- a/sync/sync_tests.gypi
+++ b/sync/sync_tests.gypi
@@ -321,12 +321,9 @@
         'internal_api/public/util/proto_value_ptr_unittest.cc',
         'internal_api/public/util/weak_handle_unittest.cc',
         'internal_api/shared_model_type_processor_unittest.cc',
-        'internal_api/sync_backup_manager_unittest.cc',
         'internal_api/sync_context_proxy_impl_unittest.cc',
         'internal_api/sync_encryption_handler_impl_unittest.cc',
         'internal_api/sync_manager_impl_unittest.cc',
-        'internal_api/sync_rollback_manager_base_unittest.cc',
-        'internal_api/sync_rollback_manager_unittest.cc',
         'internal_api/syncapi_server_connection_manager_unittest.cc',
         'js/js_event_details_unittest.cc',
         'js/sync_js_controller_unittest.cc',
@@ -335,7 +332,6 @@
         'sessions/model_type_registry_unittest.cc',
         'sessions/nudge_tracker_unittest.cc',
         'sessions/status_controller_unittest.cc',
-        'syncable/deferred_on_disk_directory_backing_store_unittest.cc',
         'syncable/directory_backing_store_unittest.cc',
         'syncable/directory_unittest.cc',
         'syncable/directory_unittest.h',
diff --git a/sync/syncable/deferred_on_disk_directory_backing_store.cc b/sync/syncable/deferred_on_disk_directory_backing_store.cc
deleted file mode 100644
index 5e960d2..0000000
--- a/sync/syncable/deferred_on_disk_directory_backing_store.cc
+++ /dev/null
@@ -1,72 +0,0 @@
-// Copyright 2014 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/deferred_on_disk_directory_backing_store.h"
-
-#include "base/logging.h"
-#include "base/metrics/histogram.h"
-#include "base/stl_util.h"
-#include "sync/syncable/syncable-inl.h"
-
-namespace syncer {
-namespace syncable {
-
-DeferredOnDiskDirectoryBackingStore::DeferredOnDiskDirectoryBackingStore(
-    const std::string& dir_name,
-    const base::FilePath& backing_file_path)
-    : OnDiskDirectoryBackingStore(dir_name, backing_file_path),
-      created_on_disk_(false) {
-}
-
-DeferredOnDiskDirectoryBackingStore::~DeferredOnDiskDirectoryBackingStore() {}
-
-bool DeferredOnDiskDirectoryBackingStore::SaveChanges(
-    const Directory::SaveChangesSnapshot& snapshot) {
-  DCHECK(CalledOnValidThread());
-
-  // Back out early if there is nothing to save.
-  if (!snapshot.HasUnsavedMetahandleChanges()) {
-    return true;
-  }
-  if (!created_on_disk_ && !CreateOnDisk())
-    return false;
-  return OnDiskDirectoryBackingStore::SaveChanges(snapshot);
-}
-
-bool DeferredOnDiskDirectoryBackingStore::CreateOnDisk() {
-  DCHECK(CalledOnValidThread());
-  DCHECK(!created_on_disk_);
-  ResetAndCreateConnection();
-  if (!base::DeleteFile(backing_file_path(), false))
-    return false;
-  if (!Open(backing_file_path()) || !InitializeTables())
-    return false;
-  created_on_disk_ = true;
-  return true;
-}
-
-DirOpenResult DeferredOnDiskDirectoryBackingStore::Load(
-    Directory::MetahandlesMap* handles_map,
-    JournalIndex* delete_journals,
-    MetahandleSet* metahandles_to_purge,
-    Directory::KernelLoadInfo* kernel_load_info) {
-  DCHECK(CalledOnValidThread());
-  // Open an in-memory database at first to create initial sync data needed by
-  // Directory.
-  CHECK(!IsOpen());
-  if (!OpenInMemory())
-    return FAILED_OPEN_DATABASE;
-
-  if (!InitializeTables())
-    return FAILED_OPEN_DATABASE;
-  if (!LoadEntries(handles_map, metahandles_to_purge))
-    return FAILED_DATABASE_CORRUPT;
-  if (!LoadInfo(kernel_load_info))
-    return FAILED_DATABASE_CORRUPT;
-
-  return OPENED;
-}
-
-}  // namespace syncable
-}  // namespace syncer
diff --git a/sync/syncable/deferred_on_disk_directory_backing_store.h b/sync/syncable/deferred_on_disk_directory_backing_store.h
deleted file mode 100644
index 0531737..0000000
--- a/sync/syncable/deferred_on_disk_directory_backing_store.h
+++ /dev/null
@@ -1,49 +0,0 @@
-// Copyright 2014 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.
-
-#ifndef SYNC_SYNCABLE_DEFERRED_ON_DISK_DIRECTORY_BACKING_STORE_H_
-#define SYNC_SYNCABLE_DEFERRED_ON_DISK_DIRECTORY_BACKING_STORE_H_
-
-#include <string>
-
-#include "base/files/file_path.h"
-#include "base/macros.h"
-#include "sync/base/sync_export.h"
-#include "sync/syncable/on_disk_directory_backing_store.h"
-
-namespace syncer {
-namespace syncable {
-
-// Store used for backing up user's data before first sync. It creates an
-// in-memory store first and switch to on-disk store if SaveChanges() is
-// called, which only happens when SyncBackupManager is shut down and a
-// syncing backend is to be created. Thus we guarantee that user data is not
-// persisted until user is actually going to sync.
-class SYNC_EXPORT DeferredOnDiskDirectoryBackingStore
-    : public OnDiskDirectoryBackingStore {
- public:
-  DeferredOnDiskDirectoryBackingStore(const std::string& dir_name,
-                                      const base::FilePath& backing_file_path);
-  ~DeferredOnDiskDirectoryBackingStore() override;
-  DirOpenResult Load(Directory::MetahandlesMap* handles_map,
-                     JournalIndex* delete_journals,
-                     MetahandleSet* metahandles_to_purge,
-                     Directory::KernelLoadInfo* kernel_load_info) override;
-  bool SaveChanges(const Directory::SaveChangesSnapshot& snapshot) override;
-
- private:
-  // Create an on-disk directory backing store. Returns true on success, false
-  // on error.
-  bool CreateOnDisk();
-
-  // Whether an on-disk directory backing store has been created.
-  bool created_on_disk_;
-
-  DISALLOW_COPY_AND_ASSIGN(DeferredOnDiskDirectoryBackingStore);
-};
-
-}  // namespace syncable
-}  // namespace syncer
-
-#endif  // SYNC_SYNCABLE_DEFERRED_ON_DISK_DIRECTORY_BACKING_STORE_H_
diff --git a/sync/syncable/deferred_on_disk_directory_backing_store_unittest.cc b/sync/syncable/deferred_on_disk_directory_backing_store_unittest.cc
deleted file mode 100644
index a62060a..0000000
--- a/sync/syncable/deferred_on_disk_directory_backing_store_unittest.cc
+++ /dev/null
@@ -1,117 +0,0 @@
-// Copyright 2014 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 "base/files/scoped_temp_dir.h"
-#include "base/message_loop/message_loop.h"
-#include "base/stl_util.h"
-#include "sync/syncable/deferred_on_disk_directory_backing_store.h"
-#include "sync/syncable/directory.h"
-#include "sync/syncable/entry_kernel.h"
-#include "sync/syncable/on_disk_directory_backing_store.h"
-#include "sync/syncable/syncable_delete_journal.h"
-#include "testing/gtest/include/gtest/gtest.h"
-
-namespace syncer {
-namespace syncable {
-namespace {
-
-static const base::FilePath::CharType kSyncDataFolderName[] =
-    FILE_PATH_LITERAL("Sync Data");
-
-class DeferredOnDiskDirectoryBackingStoreTest : public testing::Test {
- protected:
-  void SetUp() override {
-    CHECK(temp_dir_.CreateUniqueTempDir());
-    db_path_ = temp_dir_.path().Append(kSyncDataFolderName);
-  }
-
-  void TearDown() override { STLDeleteValues(&handles_map_); }
-
-  base::MessageLoop message_loop_;
-  base::ScopedTempDir temp_dir_;
-  base::FilePath db_path_;
-  Directory::MetahandlesMap handles_map_;
-  JournalIndex delete_journals_;
-  MetahandleSet metahandles_to_purge_;
-  Directory::KernelLoadInfo kernel_load_info_;
-};
-
-// Test initialization of root entry when calling Load().
-TEST_F(DeferredOnDiskDirectoryBackingStoreTest, Load) {
-  DeferredOnDiskDirectoryBackingStore store("test", db_path_);
-  EXPECT_EQ(OPENED, store.Load(&handles_map_, &delete_journals_,
-                               &metahandles_to_purge_, &kernel_load_info_));
-  EXPECT_TRUE(delete_journals_.empty());
-  EXPECT_TRUE(metahandles_to_purge_.empty());
-  ASSERT_EQ(1u, handles_map_.size());   // root node
-  ASSERT_TRUE(handles_map_.count(1));
-  EntryKernel* root = handles_map_[1];
-  EXPECT_TRUE(root->ref(ID).IsRoot());
-  EXPECT_EQ(1, root->ref(META_HANDLE));
-  EXPECT_TRUE(root->ref(IS_DIR));
-}
-
-// Test on-disk DB is not created if SaveChanges() is not called.
-TEST_F(DeferredOnDiskDirectoryBackingStoreTest,
-       DontPersistIfSavingChangesNotCalled) {
-  {
-    // Open and close.
-    DeferredOnDiskDirectoryBackingStore store("test", db_path_);
-    EXPECT_EQ(OPENED, store.Load(&handles_map_, &delete_journals_,
-                                 &metahandles_to_purge_, &kernel_load_info_));
-  }
-
-  EXPECT_FALSE(base::PathExists(db_path_));
-}
-
-// Test on-disk DB is not created when there are no changes.
-TEST_F(DeferredOnDiskDirectoryBackingStoreTest,
-       DontPersistWhenSavingNoChanges) {
-  {
-    // Open and close.
-    DeferredOnDiskDirectoryBackingStore store("test", db_path_);
-    EXPECT_EQ(OPENED, store.Load(&handles_map_, &delete_journals_,
-                                 &metahandles_to_purge_, &kernel_load_info_));
-
-    Directory::SaveChangesSnapshot snapshot;
-    store.SaveChanges(snapshot);
-  }
-
-  EXPECT_FALSE(base::PathExists(db_path_));
-}
-
-// Test changes are persisted to disk when SaveChanges() is called.
-TEST_F(DeferredOnDiskDirectoryBackingStoreTest, PersistWhenSavingValidChanges) {
-  {
-    // Open and close.
-    DeferredOnDiskDirectoryBackingStore store("test", db_path_);
-    EXPECT_EQ(OPENED, store.Load(&handles_map_, &delete_journals_,
-                                 &metahandles_to_purge_, &kernel_load_info_));
-
-    Directory::SaveChangesSnapshot snapshot;
-    EntryKernel* entry = new EntryKernel();
-    entry->put(ID, Id::CreateFromClientString("test_entry"));
-    entry->put(META_HANDLE, 2);
-    entry->mark_dirty(NULL);
-    snapshot.dirty_metas.insert(entry);
-    store.SaveChanges(snapshot);
-  }
-
-  STLDeleteValues(&handles_map_);
-
-  ASSERT_TRUE(base::PathExists(db_path_));
-  OnDiskDirectoryBackingStore read_store("test", db_path_);
-  EXPECT_EQ(OPENED,
-            read_store.Load(&handles_map_, &delete_journals_,
-                            &metahandles_to_purge_, &kernel_load_info_));
-  ASSERT_EQ(2u, handles_map_.size());
-  ASSERT_TRUE(handles_map_.count(1));     // root node
-  ASSERT_TRUE(handles_map_.count(2));
-  EntryKernel* entry = handles_map_[2];
-  EXPECT_EQ(Id::CreateFromClientString("test_entry"), entry->ref(ID));
-}
-
-}  // namespace
-}  // namespace syncable
-}  // namespace syncer
diff --git a/sync/tools/sync_client.cc b/sync/tools/sync_client.cc
index deba666..36c7561 100644
--- a/sync/tools/sync_client.cc
+++ b/sync/tools/sync_client.cc
@@ -396,7 +396,7 @@ int SyncClientMain(int argc, char* argv[]) {
   workers.push_back(passive_model_safe_worker);
 
   // Set up sync manager.
-  SyncManagerFactory sync_manager_factory(SyncManagerFactory::NORMAL);
+  SyncManagerFactory sync_manager_factory;
   scoped_ptr<SyncManager> sync_manager =
       sync_manager_factory.CreateSyncManager("sync_client manager");
   LoggingJsEventHandler js_event_handler;