Implement native web notifications for mac

chrome/browser/notifications/notification_ui_manager.h

Index: chrome/browser/notifications/notification_ui_manager.h
diff --git a/chrome/browser/notifications/notification_ui_manager.h b/chrome/browser/notifications/notification_ui_manager.h
index 5986a53382aedbc80d41f721f735a8bf6aab66f5..a3526cfb7351ed0888c4510239a54352ac195b8f 100644
--- a/chrome/browser/notifications/notification_ui_manager.h
+++ b/chrome/browser/notifications/notification_ui_manager.h
@@ -45,6 +45,14 @@ class NotificationUIManager {
   // crbug.com/530376
   static NotificationUIManager* Create(PrefService* local_state);
 
+  // Some platforms can integrate notifications with their own
+  // notification center. In those cases it will return a pointer
+  // to the object dealing with OS specific notifications which will
+  // be owned by the caller.
+  // Otherwise it will return null and chrome notifications will be
+  // used instead.
+  static NotificationUIManager* CreateNativeNotificationManager();
+
   // Adds a notification to be displayed. Virtual for unit test override.
   virtual void Add(const Notification& notification, Profile* profile) = 0;