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

components/offline_pages/background/offliner_factory_stub.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_OFFLINER_FACTORY_STUB_H_
-#define COMPONENTS_OFFLINE_PAGES_BACKGROUND_OFFLINER_FACTORY_STUB_H_
-
-#include <memory>
-
-#include "components/offline_pages/background/offliner_factory.h"
-
-namespace offline_pages {
-
-class OfflinerStub;
-
-// Test class stubbing out the functionality of OfflinerFactory.
-// It is only used for test support.
-class OfflinerFactoryStub : public OfflinerFactory {
- public:
-  OfflinerFactoryStub();
-  ~OfflinerFactoryStub() override;
-
-  Offliner* GetOffliner(const OfflinerPolicy* policy) override;
-
- private:
-  std::unique_ptr<OfflinerStub> offliner_;
-};
-
-}  // namespace offline_pages
-
-#endif  // COMPONENTS_OFFLINE_PAGES_BACKGROUND_OFFLINER_FACTORY_STUB_H_