Implement support for closing mac native notifications

chrome/browser/ui/cocoa/notifications/BUILD.gn

 # 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.
 
 import("//build/util/branding.gni")
 import("//build/config/mac/rules.gni")
 
 mac_app_bundle("alert_notification_xpc_service") {
   output_name = "AlertNotificationService"
   package_type = "xpc"
@@ skipping 31 matching lines @@
   }
 }
 
 static_library("common") {
   sources = [
     "notification_builder_mac.h",
     "notification_builder_mac.mm",
     "notification_constants_mac.h",
     "notification_constants_mac.mm",
     "notification_delivery.h",
+    "notification_private_mac.h",
     "notification_response_builder_mac.h",
     "notification_response_builder_mac.mm",
   ]
 
   deps = [
     "//base:base",
   ]
 }