[sync] skeleton implementation of TypedURLSyncBridge

components/history/core/browser/typed_url_sync_bridge.cc

Index: components/history/core/browser/typed_url_sync_bridge.cc
diff --git a/components/history/core/browser/typed_url_sync_bridge.cc b/components/history/core/browser/typed_url_sync_bridge.cc
new file mode 100644
index 0000000000000000000000000000000000000000..55712c82cb727b042063a46f805db802777aa636
--- /dev/null
+++ b/components/history/core/browser/typed_url_sync_bridge.cc
@@ -0,0 +1,103 @@
+// Copyright 2017 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/history/core/browser/typed_url_sync_bridge.h"
+
+namespace history {
+
+TypedURLSyncBridge::TypedURLSyncBridge(
+    HistoryBackend* history_backend,
+    const ChangeProcessorFactory& change_processor_factory)
+    : ModelTypeSyncBridge(change_processor_factory, syncer::TYPED_URLS),
+      history_backend_(history_backend) {
+  DCHECK(history_backend_);
+  DCHECK(sequence_checker_.CalledOnValidSequence());
+  NOTIMPLEMENTED();
+}
+
+TypedURLSyncBridge::~TypedURLSyncBridge() {
+  // TODO(gangwu): unregister as HistoryBackendObserver, can use  ScopedObserver
+  // to do it.
+}
+
+std::unique_ptr<syncer::MetadataChangeList>
+TypedURLSyncBridge::CreateMetadataChangeList() {
+  DCHECK(sequence_checker_.CalledOnValidSequence());
+  NOTIMPLEMENTED();
+  return {};
+}
+
+base::Optional<syncer::ModelError> TypedURLSyncBridge::MergeSyncData(
+    std::unique_ptr<syncer::MetadataChangeList> metadata_change_list,
+    syncer::EntityDataMap entity_data_map) {
+  DCHECK(sequence_checker_.CalledOnValidSequence());
+  NOTIMPLEMENTED();
+  return {};
+}
+
+base::Optional<syncer::ModelError> TypedURLSyncBridge::ApplySyncChanges(
+    std::unique_ptr<syncer::MetadataChangeList> metadata_change_list,
+    syncer::EntityChangeList entity_changes) {
+  DCHECK(sequence_checker_.CalledOnValidSequence());
+  NOTIMPLEMENTED();
+  return {};
+}
+
+void TypedURLSyncBridge::GetData(StorageKeyList storage_keys,
+                                 DataCallback callback) {
+  DCHECK(sequence_checker_.CalledOnValidSequence());
+  NOTIMPLEMENTED();
+}
+
+void TypedURLSyncBridge::GetAllData(DataCallback callback) {
+  DCHECK(sequence_checker_.CalledOnValidSequence());
+  NOTIMPLEMENTED();
+}
+
+// Must be exactly the value of GURL::spec() for backwards comparability with
+// the previous (Directory + SyncableService) iteration of sync integration.
+// This can be large but it is assumed that this is not held in memory at steady
+// state.
+std::string TypedURLSyncBridge::GetClientTag(
+    const syncer::EntityData& entity_data) {
+  DCHECK(sequence_checker_.CalledOnValidSequence());
+  NOTIMPLEMENTED();
+  return std::string();
+}
+
+// Prefer to use URLRow::id() to uniquely identify entities when coordinating
+// with sync because it has a significantly low memory cost than a URL.
+std::string TypedURLSyncBridge::GetStorageKey(
+    const syncer::EntityData& entity_data) {
+  DCHECK(sequence_checker_.CalledOnValidSequence());
+  NOTIMPLEMENTED();
+  return std::string();
+}
+
+void TypedURLSyncBridge::OnURLVisited(history::HistoryBackend* history_backend,
+                                      ui::PageTransition transition,
+                                      const history::URLRow& row,
+                                      const history::RedirectList& redirects,
+                                      base::Time visit_time) {
+  DCHECK(sequence_checker_.CalledOnValidSequence());
+  NOTIMPLEMENTED();
+}
+
+void TypedURLSyncBridge::OnURLsModified(
+    history::HistoryBackend* history_backend,
+    const history::URLRows& changed_urls) {
+  DCHECK(sequence_checker_.CalledOnValidSequence());
+  NOTIMPLEMENTED();
+}
+
+void TypedURLSyncBridge::OnURLsDeleted(history::HistoryBackend* history_backend,
+                                       bool all_history,
+                                       bool expired,
+                                       const history::URLRows& deleted_rows,
+                                       const std::set<GURL>& favicon_urls) {
+  DCHECK(sequence_checker_.CalledOnValidSequence());
+  NOTIMPLEMENTED();
+}
+
+}  // namespace history