Move all components/offline_pages/ files into component/offline_pages/core

components/offline_pages/background/mark_attempt_started_task.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_OFFLINE_PAGES_BACKGROUND_MARK_ATTEMPT_STARTED_TASK_H_
-#define COMPONENTS_OFFLINE_PAGES_BACKGROUND_MARK_ATTEMPT_STARTED_TASK_H_
-
-#include <stdint.h>
-
-#include "components/offline_pages/background/update_request_task.h"
-#include "components/offline_pages/core/task.h"
-
-namespace offline_pages {
-
-class RequestQueueStore;
-
-class MarkAttemptStartedTask : public UpdateRequestTask {
- public:
-  MarkAttemptStartedTask(RequestQueueStore* store,
-                         int64_t request_id,
-                         const RequestQueueStore::UpdateCallback& callback);
-  ~MarkAttemptStartedTask() override;
-
- protected:
-  // UpdateRequestTask implementation:
-  void UpdateRequestImpl(std::unique_ptr<UpdateRequestsResult> result) override;
-};
-
-}  // namespace offline_pages
-
-#endif  // COMPONENTS_OFFLINE_PAGES_BACKGROUND_MARK_ATTEMPT_STARTED_TASK_H_