WIP: Pref service user prefs.

services/preferences/user_prefs_factory.h

Index: services/preferences/user_prefs_factory.h
diff --git a/services/preferences/user_prefs_factory.h b/services/preferences/user_prefs_factory.h
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index 0000000000000000000000000000000000000000..367b2d40f37cb439eef1b11ac815e00d7f296948
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+++ b/services/preferences/user_prefs_factory.h
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+// 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 SERVICES_PREFERENCES_USER_PREFS_FACTORY_H_
+#define SERVICES_PREFERENCES_USER_PREFS_FACTORY_H_
+
+#include "services/preferences/public/interfaces/preferences.mojom.h"
+
+namespace base {
+class SequencedWorkerPool;
+}
+
+namespace prefs {
+class UserPrefs;
+
+// Create a new mojom::PersistentPrefStore impl that runs on |worker_pool|
+// configured by |configuration|.
+std::unique_ptr<UserPrefs> CreateUserPrefs(
+    mojom::UserPrefsConfigurationPtr configuration,
+    base::SequencedWorkerPool* worker_pool);
+
+}  // namespace prefs
+
+#endif  // SERVICES_PREFERENCES_USER_PREFS_FACTORY_H_