Remove unused arc_notifier_manager.h.

chrome/browser/notifications/arc_notifier_manager.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 CHROME_BROWSER_NOTIFICATIONS_ARC_NOTIFIER_MANAGER_H_
-#define CHROME_BROWSER_NOTIFICATIONS_ARC_NOTIFIER_MANAGER_H_
-
-#include <memory>
-#include <string>
-#include <vector>
-
-#include "base/macros.h"
-
-namespace content {
-class BrowserContext;
-}
-
-namespace message_center {
-struct Notifier;
-}
-
-namespace arc {
-
-// TODO(hirono): Observe enabled flag change and notify it to message center.
-class ArcNotifierManager {
- public:
-  ArcNotifierManager() {}
-
-  // TODO(hirono): Rewrite the function with new API to fetch package list.
-  std::vector<std::unique_ptr<message_center::Notifier>> GetNotifiers(
-      content::BrowserContext* profile);
-  void SetNotifierEnabled(const std::string& package, bool enabled);
-
- private:
-  DISALLOW_COPY_AND_ASSIGN(ArcNotifierManager);
-};
-
-}  // namespace arc
-
-#endif  // CHROME_BROWSER_NOTIFICATIONS_ARC_NOTIFIER_MANAGER_H_