Beginnings of synchronizing notifications in the notification database.

content/public/browser/platform_notification_service.h

 // Copyright 2014 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 CONTENT_PUBLIC_BROWSER_PLATFORM_NOTIFICATION_SERVICE_H_
 #define CONTENT_PUBLIC_BROWSER_PLATFORM_NOTIFICATION_SERVICE_H_
 
 #include <stdint.h>
+#include <set>
 #include <string>
 
 #include "base/callback_forward.h"
 #include "base/memory/scoped_ptr.h"
 #include "content/common/content_export.h"
 #include "third_party/WebKit/public/platform/modules/notifications/WebNotificationPermission.h"
 
 class GURL;
 class SkBitmap;
 
@@ skipping 46 matching lines @@
       int64_t persistent_notification_id,
       const GURL& origin,
       const SkBitmap& icon,
       const PlatformNotificationData& notification_data) = 0;
 
   // Closes the persistent notification identified by
   // |persistent_notification_id|. This method must be called on the UI thread.
   virtual void ClosePersistentNotification(
       BrowserContext* browser_context,
       int64_t persistent_notification_id) = 0;
+
+  // Writes the ids of all currently displaying persistent notifications for the
+  // given |browser_context| to |displayed_notifications|. Returns whether the
+  // platform is able to provide such a set.
+  virtual bool GetDisplayedPersistentNotifications(
+      BrowserContext* browser_context,
+      std::set<std::string>* displayed_notifications) = 0;
 };
 
 }  // namespace content
 
 #endif  // CONTENT_PUBLIC_BROWSER_PLATFORM_NOTIFICATION_SERVICE_H_