Add support for native extension notifications

chrome/browser/extensions/api/notifications/extension_notification_handler.cc

 // 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.
 
 #include "chrome/browser/extensions/api/notifications/extension_notification_handler.h"
 
-#include "base/logging.h"
-
-ExtensionNotificationHandler::ExtensionNotificationHandler() = default;
+ExtensionNotificationHandler::ExtensionNotificationHandler()
+    : NonPersistentNotificationHandler() {}
 
 ExtensionNotificationHandler::~ExtensionNotificationHandler() = default;
 
-void ExtensionNotificationHandler::OnClose(Profile* profile,
-                                           const std::string& origin,
-                                           const std::string& notification_id,
-                                           bool by_user) {
-  // TODO(peter): Call EraseDataForNotificationId from here once this event
-  // can be relied upon. (It's only been implemented for native NDSes.)
-}
-
-void ExtensionNotificationHandler::OnClick(
-    Profile* profile,
-    const std::string& origin,
-    const std::string& notification_id,
-    int action_index,
-    const base::NullableString16& reply) {}
-
 void ExtensionNotificationHandler::OpenSettings(Profile* profile) {
   // Extension notifications don't display a settings button.
   NOTREACHED();
 }
-
-void ExtensionNotificationHandler::RegisterNotification(
-    const std::string& notification_id,
-    NotificationDelegate* delegate) {}