[Offline Pages] Introducing StorageManagerClient interface.

components/offline_pages/storage_manager_client.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_STORAGE_MANAGER_CLIENT_H_
+#define COMPONENTS_OFFLINE_PAGES_STORAGE_MANAGER_CLIENT_H_
+
+#include <stdint.h>
+
+#include <vector>
+
+#include "base/callback.h"
+#include "components/offline_pages/offline_page_types.h"
+
+namespace offline_pages {
+
+class ClientPolicyController;
+struct OfflinePageItem;
+
+// This is an interface for offline page model to implement, in order to

[fgorski, 2016/05/11 22:39:00]

This interface should presume no knowledge or existence of offline page model.

This interface should be implemented by clients managed by storage manager.

Also, when you remove 2 bottom methods, per suggestion, you can move the
definition of the interface to inside of the StorageManager, and simply call it
Client as the outer class will scope the name well.

[romax, 2016/05/11 23:54:58]

Acknowledged.

+// provide the functionalities for storage manager.
+class StorageManagerClient {
+ public:
+  // Asks the client to get all offline pages and invoke |callback|.
+  virtual void GetAllPages(const MultipleOfflinePageItemCallback& callback) = 0;
+
+  // Asks the client to delete pages based on |offline_ids| and invoke
+  // |callback|.
+  virtual void DeletePagesByOfflineId(const std::vector<int64_t>& offline_ids,
+                                      const DeletePageCallback& callback) = 0;
+
+  // Get the policy controller from the client.
+  virtual ClientPolicyController* GetPolicyController() = 0;
+
+  // Returns true if the client is fully loaded.
+  virtual bool IsLoaded() const = 0;
+};
+
+}  // namespace offline_pages
+
+#endif  // COMPONENTS_OFFLINE_PAGES_STORAGE_MANAGER_CLIENT_H_