[Sync] Implements the loopback sync server.

components/sync/engine_impl/loopback_server/persistent_unique_client_entity.cc

Index: components/sync/engine_impl/loopback_server/persistent_unique_client_entity.cc
diff --git a/components/sync/engine_impl/loopback_server/persistent_unique_client_entity.cc b/components/sync/engine_impl/loopback_server/persistent_unique_client_entity.cc
new file mode 100644
index 0000000000000000000000000000000000000000..e6a8c07722114b0c089a04e78e4ccfc7e8673dfd
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+++ b/components/sync/engine_impl/loopback_server/persistent_unique_client_entity.cc
@@ -0,0 +1,92 @@
+// 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 "components/sync/engine_impl/loopback_server/persistent_unique_client_entity.h"
+
+#include <stdint.h>
+
+#include <memory>
+#include <string>
+
+#include "base/guid.h"
+#include "components/sync/base/model_type.h"
+#include "components/sync/engine_impl/loopback_server/loopback_server_entity.h"
+#include "components/sync/engine_impl/loopback_server/persistent_permanent_entity.h"
+#include "components/sync/protocol/sync.pb.h"
+#include "components/sync/syncable/syncable_util.h"
+
+using std::string;
+
+using syncer::GetModelTypeFromSpecifics;
+using syncer::ModelType;
+using syncer::syncable::GenerateSyncableHash;
+
+namespace syncer {
+
+PersistentUniqueClientEntity::PersistentUniqueClientEntity(
+    const string& id,
+    ModelType model_type,
+    int64_t version,
+    const string& name,
+    const string& client_defined_unique_tag,
+    const sync_pb::EntitySpecifics& specifics,
+    int64_t creation_time,
+    int64_t last_modified_time)
+    : LoopbackServerEntity(id, model_type, version, name),
+      client_defined_unique_tag_(client_defined_unique_tag),
+      creation_time_(creation_time),
+      last_modified_time_(last_modified_time) {
+  SetSpecifics(specifics);
+}
+
+PersistentUniqueClientEntity::~PersistentUniqueClientEntity() {}
+
+// static
+std::unique_ptr<LoopbackServerEntity> PersistentUniqueClientEntity::Create(
+    const sync_pb::SyncEntity& client_entity) {
+  CHECK(client_entity.has_client_defined_unique_tag())
+      << "A PersistentUniqueClientEntity must have a client-defined unique "
+         "tag.";
+  ModelType model_type =
+      syncer::GetModelTypeFromSpecifics(client_entity.specifics());
+  string id = EffectiveIdForClientTaggedEntity(client_entity);
+  return std::unique_ptr<LoopbackServerEntity>(new PersistentUniqueClientEntity(
+      id, model_type, client_entity.version(), client_entity.name(),
+      client_entity.client_defined_unique_tag(), client_entity.specifics(),
+      client_entity.ctime(), client_entity.mtime()));
+}
+
+// static
+std::string PersistentUniqueClientEntity::EffectiveIdForClientTaggedEntity(
+    const sync_pb::SyncEntity& entity) {
+  return LoopbackServerEntity::CreateId(
+      syncer::GetModelTypeFromSpecifics(entity.specifics()),
+      entity.client_defined_unique_tag());
+}
+
+bool PersistentUniqueClientEntity::RequiresParentId() const {
+  return false;
+}
+
+string PersistentUniqueClientEntity::GetParentId() const {
+  // The parent ID for this type of entity should always be its ModelType's
+  // root node.
+  return LoopbackServerEntity::GetTopLevelId(GetModelType());
+}
+
+sync_pb::LoopbackServerEntity_Type
+PersistentUniqueClientEntity::GetLoopbackServerEntityType() const {
+  return sync_pb::LoopbackServerEntity_Type_UNIQUE;
+}
+
+void PersistentUniqueClientEntity::SerializeAsProto(
+    sync_pb::SyncEntity* proto) const {
+  LoopbackServerEntity::SerializeBaseProtoFields(proto);
+
+  proto->set_client_defined_unique_tag(client_defined_unique_tag_);
+  proto->set_ctime(creation_time_);
+  proto->set_mtime(last_modified_time_);
+}
+
+}  // namespace syncer