Switch to standard integer types in chrome/browser/, part 2 of 4.

chrome/browser/notifications/notification_system_observer.h

 // Copyright 2013 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_NOTIFICATION_SYSTEM_OBSERVER_H_
 #define CHROME_BROWSER_NOTIFICATIONS_NOTIFICATION_SYSTEM_OBSERVER_H_
 
+#include "base/macros.h"
 #include "content/public/browser/notification_observer.h"
 #include "content/public/browser/notification_registrar.h"
 
 class NotificationUIManager;
 
 // The content::NotificationObserver observes system status change and sends
 // events to NotificationUIManager.
 class NotificationSystemObserver : public content::NotificationObserver {
  public:
   explicit NotificationSystemObserver(NotificationUIManager* ui_manager);
   ~NotificationSystemObserver() override;
 
  protected:
   // content::NotificationObserver override.
   void Observe(int type,
                const content::NotificationSource& source,
                const content::NotificationDetails& details) override;
 
  private:
   // Registrar for the other kind of notifications (event signaling).
   content::NotificationRegistrar registrar_;
   NotificationUIManager* ui_manager_;
 
   DISALLOW_COPY_AND_ASSIGN(NotificationSystemObserver);
 };
 
 #endif  // CHROME_BROWSER_NOTIFICATIONS_NOTIFICATION_SYSTEM_OBSERVER_H_