Add initial support for native Linux desktop notifications

chrome/browser/notifications/notification_platform_bridge.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_NOTIFICATION_PLATFORM_BRIDGE_H_
 #define CHROME_BROWSER_NOTIFICATIONS_NOTIFICATION_PLATFORM_BRIDGE_H_
 
+#include <memory>
 #include <set>
 #include <string>
 
 #include "base/callback_forward.h"
 #include "base/macros.h"
 #include "chrome/browser/notifications/notification_common.h"
 
 class Notification;
 
 // Provides the low-level interface that enables notifications to be displayed
@@ skipping 30 matching lines @@
       const DisplayedNotificationsCallback& callback) const = 0;
 
  protected:
   NotificationPlatformBridge() {}
 
  private:
   DISALLOW_COPY_AND_ASSIGN(NotificationPlatformBridge);
 };
 
 #endif  // CHROME_BROWSER_NOTIFICATIONS_NOTIFICATION_PLATFORM_BRIDGE_H_