Add initial support for native Linux desktop notifications

chrome/browser/notifications/dbus_notification_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_DBUS_NOTIFICATION_MANAGER_H_
+#define CHROME_BROWSER_NOTIFICATIONS_DBUS_NOTIFICATION_MANAGER_H_
+
+#include <gio/gio.h>
+
+#include "base/macros.h"
+#include "ui/message_center/message_center.h"
+#include "ui/message_center/message_center_observer.h"
+
+class DbusNotificationManager : public message_center::MessageCenterObserver {
+ public:
+  // Returns a new DbusNotificationManager if system notifications are
+  // supported, otherwise returns nullptr.
+  static DbusNotificationManager* CreateDbusNotificationManager(
+      message_center::MessageCenter* message_center);
+
+  ~DbusNotificationManager() override;
+
+  // Overridden from message_center::MessageCenterObserver.
+  void OnNotificationAdded(const std::string& notification_id) override;
+  void OnNotificationRemoved(const std::string& notification_id,
+                             bool by_user) override;
+  void OnNotificationUpdated(const std::string& notification_id) override;
+
+ private:
+  DbusNotificationManager(message_center::MessageCenter* message_center,
+                          GDBusProxy* notification_proxy);
+
+  message_center::MessageCenter* message_center_;
+
+  GDBusProxy* notification_proxy_;
+
+  DISALLOW_COPY_AND_ASSIGN(DbusNotificationManager);
+};
+
+#endif  // CHROME_BROWSER_NOTIFICATIONS_DBUS_NOTIFICATION_MANAGER_H_