Add skeletons for the factories to create the request coordinator and

components/offline_pages/background/prerenderer_offliner_factory.h

+// 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.
+
+#ifndef COMPONENTS_OFFLINE_PAGES_BACKGROUND_PRERENDERER_OFFLINER_FACTORY_H_
+#define COMPONENTS_OFFLINE_PAGES_BACKGROUND_PRERENDERER_OFFLINER_FACTORY_H_
+
+#include "base/macros.h"
+#include "components/offline_pages/background/offliner.h"
+#include "components/offline_pages/background/offliner_factory.h"
+#include "components/offline_pages/background/prerenderer_offliner.h"
+
+namespace base {
+template <typename T>
+struct DefaultSingletonTraits;
+}  // namespace base
+
+namespace offline_pages {
+
+class OfflinerPolicy;
+class PrerendererOffliner;
+
+// A factory to create one unique OfflinePageModel.
+class PrerendererOfflinerFactory : public OfflinerFactory {

[fgorski, 2016/04/29 04:16:46]

This should be in the c/b/a/op/ with the prerendering_offliner implementation.

+ public:
+  PrerendererOffliner* GetInstance(OfflinerPolicy* policy) override;

[fgorski, 2016/04/29 04:16:46]

Are you going for a model, where offliners are going to be singletons?
This is a bit risky, knowing that some of them could be working in parallel.

I think you are trying to mimic the keyed service factory and we might not need
that.

+
+  PrerendererOfflinerFactory();
+  ~PrerendererOfflinerFactory() override;
+
+ private:
+  friend struct base::DefaultSingletonTraits<PrerendererOfflinerFactory>;
+
+  DISALLOW_COPY_AND_ASSIGN(PrerendererOfflinerFactory);
+
+  PrerendererOffliner* offliner_;
+};
+
+}  // namespace offline_pages
+
+#endif  // COMPONENTS_OFFLINE_PAGES_BACKGROUND_PRERENDERER_OFFLINER_FACTORY_H_