Add the NotificationDatabaseData structure and protobuf

content/browser/notifications/notification_database_data.h

+// Copyright 2015 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_BROWSER_NOTIFICATIONS_NOTIFICATION_DATABASE_DATA_H_
+#define CONTENT_BROWSER_NOTIFICATIONS_NOTIFICATION_DATABASE_DATA_H_
+
+#include <stdint.h>
+
+#include "content/common/content_export.h"
+#include "content/public/common/platform_notification_data.h"
+#include "url/gurl.h"
+
+namespace content {
+
+class NotificationDatabaseDataProto;
+
+// Stores information about a Web Notification as available in the notification
+// database. Beyond the notification's own data, its id and attribution need
+// to be available for users of the database as well.
+struct CONTENT_EXPORT NotificationDatabaseData {
+  NotificationDatabaseData();
+  ~NotificationDatabaseData();
+
+  // Id of the notification as allocated by the NotificationDatabase.
+  int64_t notification_id;
+
+  // Origin of the website this notification is associated with.
+  GURL origin;
+
+  // Id of the Service Worker registration this notification is associated with.
+  int64_t service_worker_registration_id;
+
+  // Platform data of the notification that's being stored.
+  PlatformNotificationData notification_data;
+};
+
+// Converts a NotificationDatabaseData object to the protocol buffer message.
+CONTENT_EXPORT NotificationDatabaseDataProto ToNotificationDatabaseDataProto(

[Bernhard Bauer, 2015/03/12 18:11:14]

Another thing to think about: Do we even need to expose the fact that the data
is serialized to a protobuf? We could just have serialize and deserialize
methods that would handle binary data of some form (probably strings, if that's
what LevelDB takes?).

[Bernhard Bauer, 2015/03/12 18:11:14]

Could you make these methods on the struct, so they're not directly in the
content namespace?

[Peter Beverloo, 2015/03/12 21:09:52]

Done.

[Peter Beverloo, 2015/03/12 21:09:52]

Eventually I envision the NotificationDatabaseData struct to live in the content
API, which would change this functionality to be a conversion tool (similar to
content/child/notifications/notification_data_conversions.h). We wouldn't want
to expose serialization capabilities, however.

That's something for later, however.

Done.

+    const NotificationDatabaseData& database_data);
+
+// Converts a NotificationDatabaseDataProto object to the normal C++ structure.
+CONTENT_EXPORT NotificationDatabaseData ToNotificationDatabaseData(
+    const NotificationDatabaseDataProto& database_data_proto);
+
+}  // namespace content
+
+#endif  // CONTENT_BROWSER_NOTIFICATIONS_NOTIFICATION_DATABASE_DATA_H_