Prefetching: Introduce store commands abstractions to be used by tasks.

components/offline_pages/core/prefetch/store/cleanup_zombies_store_command.h

+// Copyright 2017 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_CORE_PREFETCH_STORE_CLEANUP_ZOMBIES_STORE_COMMAND_H_
+#define COMPONENTS_OFFLINE_PAGES_CORE_PREFETCH_STORE_CLEANUP_ZOMBIES_STORE_COMMAND_H_
+
+#include <string>
+#include <vector>
+
+#include "base/callback.h"
+#include "base/macros.h"
+#include "url/gurl.h"
+
+namespace offline_pages {
+
+// Cleans up URL entries in the Zombie state that are not being suggested by the
+// client anymore.
+class CleanupZombiesStoreCommand {
+ public:
+  CleanupZombiesStoreCommand(){};
+  virtual ~CleanupZombiesStoreCommand(){};
+
+  // Cleans up Zombie entries from the client's |name_space| except for the ones
+  // whose URL is contained in |urls_to_keep|.
+  virtual void Execute(const std::string& name_space,
+                       const std::vector<GURL>& urls_to_keep,
+                       base::OnceCallback<void()> callback) = 0;
+
+ private:
+  DISALLOW_COPY_AND_ASSIGN(CleanupZombiesStoreCommand);
+};
+
+}  // namespace offline_pages
+
+#endif  // COMPONENTS_OFFLINE_PAGES_CORE_PREFETCH_STORE_CLEANUP_ZOMBIES_STORE_COMMAND_H_