[sync] skeleton implementation of TypedURLSyncBridge

components/history/core/browser/history_service.h

 // Copyright (c) 2012 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_HISTORY_CORE_BROWSER_HISTORY_SERVICE_H_
 #define COMPONENTS_HISTORY_CORE_BROWSER_HISTORY_SERVICE_H_
 
 #include <stddef.h>
 #include <stdint.h>
 
@@ skipping 15 matching lines @@
 #include "base/strings/string16.h"
 #include "base/task/cancelable_task_tracker.h"
 #include "base/threading/thread_checker.h"
 #include "base/time/time.h"
 #include "build/build_config.h"
 #include "components/favicon_base/favicon_callback.h"
 #include "components/favicon_base/favicon_usage_data.h"
 #include "components/history/core/browser/delete_directive_handler.h"
 #include "components/history/core/browser/history_types.h"
 #include "components/history/core/browser/keyword_id.h"
+#include "components/history/core/browser/typed_url_sync_bridge.h"

[skym, 2017/03/07 18:08:04]

Is there a reason this file needs either the bridge or syncable service's .h
file to be included? Why not forward declare?

[Gang Wu, 2017/03/31 19:35:58]

chrome_sync_client.cc call history->GetTypedUrlSyncableService()->AsWeakPtr(),
for ->AsWeakPtr() function we need to include .h file here.

 #include "components/history/core/browser/typed_url_syncable_service.h"
 #include "components/keyed_service/core/keyed_service.h"
 #include "components/sync/model/syncable_service.h"
 #include "sql/init_status.h"
 #include "ui/base/page_transition_types.h"
 
 class GURL;
 class HistoryQuickProviderTest;
 class HistoryURLProvider;
 class InMemoryURLIndexTest;
@@ skipping 76 matching lines @@
   // database has not been loaded yet. This pointer is owned by the history
   // system. Callers should not store or cache this value.
   //
   // TODO(brettw) this should return the InMemoryHistoryBackend.
   URLDatabase* InMemoryDatabase();
 
   // Following functions get URL information from in-memory database.
   // They return false if database is not available (e.g. not loaded yet) or the
   // URL does not exist.
 
+  // Returns a pointer to the TypedURLSyncBridge owned by HistoryBackend.
+  // This method should only be called from the history thread, because the
+  // returned bridge is intended to be accessed only via the history thread.
+  TypedURLSyncBridge* GetTypedURLSyncBridge() const;
+
   // Returns a pointer to the TypedUrlSyncableService owned by HistoryBackend.
   // This method should only be called from the history thread, because the
   // returned service is intended to be accessed only via the history thread.
   TypedUrlSyncableService* GetTypedUrlSyncableService() const;
 
   // KeyedService:
   void Shutdown() override;
 
   // Callback for value asynchronously returned by
   // GetCountsAndLastVisitForOrigins().
@@ skipping 694 matching lines @@
 
   // All vended weak pointers are invalidated in Cleanup().
   base::WeakPtrFactory<HistoryService> weak_ptr_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(HistoryService);
 };
 
 }  // namespace history
 
 #endif  // COMPONENTS_HISTORY_CORE_BROWSER_HISTORY_SERVICE_H_