delete the levelDB storage implementation.

chrome/browser/android/offline_pages/offline_page_model_factory.cc

 // Copyright 2015 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 "chrome/browser/android/offline_pages/offline_page_model_factory.h"
 
 #include <utility>
 
 #include "base/files/file_path.h"
 #include "base/memory/singleton.h"
 #include "base/sequenced_task_runner.h"
 #include "chrome/browser/profiles/incognito_helpers.h"
 #include "chrome/browser/profiles/profile.h"
 #include "chrome/common/chrome_constants.h"
 #include "components/keyed_service/content/browser_context_dependency_manager.h"
 #include "components/offline_pages/offline_page_metadata_store_sql.h"
 #include "components/offline_pages/offline_page_model.h"
-#include "components/offline_pages/proto/offline_pages.pb.h"
 #include "content/public/browser/browser_thread.h"
 
 namespace offline_pages {
 
 OfflinePageModelFactory::OfflinePageModelFactory()
     : BrowserContextKeyedServiceFactory(
           "OfflinePageModel",
           BrowserContextDependencyManager::GetInstance()) {
 }
 
@@ skipping 23 matching lines @@
 
   base::FilePath archives_dir =
       profile->GetPath().Append(chrome::kOfflinePageArchviesDirname);
 
   return new OfflinePageModel(std::move(metadata_store), archives_dir,
                               background_task_runner);
 }
 
 }  // namespace offline_pages