[sync] skeleton implementation of AutocompleteSyncBridge

components/autofill/core/browser/webdata/autocomplete_sync_bridge.h

+// Copyright 2016 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 COMPONENTS_AUTOFILL_CORE_BROWSER_WEBDATA_AUTOCOMPLETE_SYNC_BRIDGE_H_
+#define COMPONENTS_AUTOFILL_CORE_BROWSER_WEBDATA_AUTOCOMPLETE_SYNC_BRIDGE_H_
+
+#include "base/scoped_observer.h"
+#include "base/supports_user_data.h"
+#include "base/threading/non_thread_safe.h"
+#include "components/autofill/core/browser/webdata/autofill_change.h"
+#include "components/autofill/core/browser/webdata/autofill_webdata_service_observer.h"
+#include "components/sync/model/metadata_change_list.h"
+#include "components/sync/model/model_type_sync_bridge.h"
+
+namespace syncer {
+class SyncError;
+}
+
+namespace autofill {
+
+class AutofillWebDataBackend;
+class AutofillWebDataService;
+
+class AutocompleteSyncBridge : public base::SupportsUserData::Data,
+                               public syncer::ModelTypeSyncBridge,
+                               public AutofillWebDataServiceObserverOnDBThread {
+ public:
+  AutocompleteSyncBridge();
+  AutocompleteSyncBridge(
+      AutofillWebDataBackend* backend,
+      const ChangeProcessorFactory& change_processor_factory);
+  ~AutocompleteSyncBridge() override;
+
+  static void CreateForWebDataServiceAndBackend(
+      AutofillWebDataService* web_data_service,
+      AutofillWebDataBackend* web_data_backend);
+
+  static AutocompleteSyncBridge* FromWebDataService(
+      AutofillWebDataService* web_data_service);
+
+  // syncer::ModelTypeService implementation.
+  std::unique_ptr<syncer::MetadataChangeList> CreateMetadataChangeList()
+      override;
+  syncer::SyncError MergeSyncData(
+      std::unique_ptr<syncer::MetadataChangeList> metadata_change_list,
+      syncer::EntityDataMap entity_data_map) override;
+  syncer::SyncError ApplySyncChanges(
+      std::unique_ptr<syncer::MetadataChangeList> metadata_change_list,
+      syncer::EntityChangeList entity_changes) override;
+  void GetData(StorageKeyList storage_keys, DataCallback callback) override;
+  void GetAllData(DataCallback callback) override;
+  // Generate a tag that uniquely identifies |entity_data| across all data
+  // types. This is used to identify the entity on the server. The format, which
+  // must remain the same for server compatibility, is:
+  // "autofill_entry|$name|$value" where $name and $value are escaped.
+  std::string GetClientTag(const syncer::EntityData& entity_data) override;
+  // Generate a string key uniquely identifying |entity_data| in the context of
+  // local storage. The format, which should stay the same, is $name|$value"
+  // where $name and $value are escaped.
+  std::string GetStorageKey(const syncer::EntityData& entity_data) override;
+
+  // AutofillWebDataServiceObserverOnDBThread implementation.
+  void AutofillEntriesChanged(const AutofillChangeList& changes) override;
+
+ private:
+  base::ThreadChecker thread_checker_;
+
+  // AutocompleteSyncBridge is owned by |web_data_backend_| through
+  // SupportsUserData, so it's guaranteed to outlive |this|.
+  AutofillWebDataBackend* const web_data_backend_;
+
+  ScopedObserver<AutofillWebDataBackend, AutocompleteSyncBridge>
+      scoped_observer_;
+};
+
+}  // namespace autofill
+
+#endif  // COMPONENTS_AUTOFILL_CORE_BROWSER_WEBDATA_AUTOCOMPLETE_SYNC_BRIDGE_H_