Add sync manager classes for backup/rollback:

sync/internal_api/sync_rollback_manager.cc

Index: sync/internal_api/sync_rollback_manager.cc
diff --git a/sync/internal_api/sync_rollback_manager.cc b/sync/internal_api/sync_rollback_manager.cc
new file mode 100644
index 0000000000000000000000000000000000000000..dc336dfc101fc229da85705c748898e205b1b189
--- /dev/null
+++ b/sync/internal_api/sync_rollback_manager.cc
@@ -0,0 +1,130 @@
+// 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 "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"
+
+namespace syncer {
+
+SyncRollbackManager::SyncRollbackManager()
+    : change_delegate_(NULL) {
+}
+
+SyncRollbackManager::~SyncRollbackManager() {
+}
+
+void SyncRollbackManager::Init(
+      const base::FilePath& database_location,
+      const WeakHandle<JsEventHandler>& event_handler,
+      const std::string& sync_server_and_path,
+      int sync_server_port,
+      bool use_ssl,
+      scoped_ptr<HttpPostProviderFactory> post_factory,
+      const std::vector<scoped_refptr<ModelSafeWorker> >& workers,
+      ExtensionsActivity* extensions_activity,
+      SyncManager::ChangeDelegate* change_delegate,
+      const SyncCredentials& credentials,
+      const std::string& invalidator_client_id,
+      const std::string& restored_key_for_bootstrapping,
+      const std::string& restored_keystore_key_for_bootstrapping,
+      InternalComponentsFactory* internal_components_factory,
+      Encryptor* encryptor,
+      scoped_ptr<UnrecoverableErrorHandler> unrecoverable_error_handler,
+      ReportUnrecoverableErrorFunction
+          report_unrecoverable_error_function,
+      CancelationSignal* cancelation_signal) {
+  SyncRollbackManagerBase::Init(database_location, event_handler,
+                                sync_server_and_path, sync_server_port,
+                                use_ssl, post_factory.Pass(),
+                                workers, extensions_activity, change_delegate,
+                                credentials, invalidator_client_id,
+                                restored_key_for_bootstrapping,
+                                restored_keystore_key_for_bootstrapping,
+                                internal_components_factory, encryptor,
+                                unrecoverable_error_handler.Pass(),
+                                report_unrecoverable_error_function,
+                                cancelation_signal);
+
+  change_delegate_ = change_delegate;

[Nicolas Zea, 2014/04/17 18:22:56]

Where do you clear the old backup directory? Or this directory for that matter
(after rollback)?

[haitaol1, 2014/04/17 19:30:38]

SyncBackendHostCore::DoShutdown() deletes the directory.

On 2014/04/17 18:22:56, Nicolas Zea wrote:

+
+  for (size_t i = 0; i < workers.size(); ++i) {
+    ModelSafeGroup group = workers[i]->GetModelSafeGroup();
+    CHECK(workers_.find(group) == workers_.end());
+    workers_[group] = workers[i];
+  }
+
+  rollback_ready_types_ = GetUserShare()->directory->InitialSyncEndedTypes();
+  rollback_ready_types_.RetainAll(BackupTypes());
+}
+
+void SyncRollbackManager::StartSyncingNormally(
+    const ModelSafeRoutingInfo& routing_info){
+  std::map<ModelType, syncable::Directory::Metahandles> to_delete;
+
+  {
+    WriteTransaction trans(FROM_HERE, GetUserShare());
+    syncable::Directory::Metahandles unsynced;
+    GetUserShare()->directory->GetUnsyncedMetaHandles(trans.GetWrappedTrans(),
+                                             &unsynced);

[Nicolas Zea, 2014/04/17 18:22:56]

fix indent (FYI, you can use git cl format to fix all these issues)

[haitaol1, 2014/04/17 19:30:38]

Done.

+    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;
+
+      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));
+  }

[Nicolas Zea, 2014/04/17 18:22:56]

add a TODO to handle any cases where data was merged at association (possibly
referencing a bug)?

[haitaol1, 2014/04/17 19:30:38]

Added TODO above.

On 2014/04/17 18:22:56, Nicolas Zea wrote:

+}
+
+SyncerError SyncRollbackManager::DeleteOnWorkerThread(
+    ModelType type, std::vector<int64> 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;
+}
+
+}  // namespace syncer