Implement the ability to get all notifications in Chromium.

content/common/platform_notification_messages.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.
 
 // Messages for platform-native notifications using the Web Notification API.
 // Multiply-included message file, hence no include guard.
 
 #include <stdint.h>
 #include <string>
 #include <utility>
 #include <vector>
 
 #include "content/public/common/platform_notification_data.h"
 #include "ipc/ipc_message_macros.h"
 #include "third_party/WebKit/public/platform/modules/notifications/WebNotificationPermission.h"
 #include "third_party/skia/include/core/SkBitmap.h"
 
 // Singly-included section for type definitions.
 #ifndef CONTENT_COMMON_PLATFORM_NOTIFICATION_MESSAGES_H_
 #define CONTENT_COMMON_PLATFORM_NOTIFICATION_MESSAGES_H_
 
 // Defines the pair of [persistent notification id] => [notification data] used
 // when getting the notifications for a given Service Worker registration.
 using PersistentNotificationInfo =
-    std::pair<std::string, content::PlatformNotificationData>;
+    std::pair<int64_t, content::PlatformNotificationData>;
 
 #endif  // CONTENT_COMMON_PLATFORM_NOTIFICATION_MESSAGES_H_
 
 #define IPC_MESSAGE_START PlatformNotificationMsgStart
 
 IPC_ENUM_TRAITS_MAX_VALUE(blink::WebNotificationPermission,
                           blink::WebNotificationPermissionLast)
 
 IPC_ENUM_TRAITS_MAX_VALUE(
     content::PlatformNotificationData::NotificationDirection,
@@ skipping 61 matching lines @@
 IPC_MESSAGE_CONTROL1(PlatformNotificationHostMsg_Close,
                      int /* notification_id */)
 
 IPC_MESSAGE_CONTROL2(PlatformNotificationHostMsg_ClosePersistent,
                      GURL /* origin */,
                      int64_t /* persistent_notification_id */)
 
 IPC_SYNC_MESSAGE_CONTROL1_1(PlatformNotificationHostMsg_CheckPermission,
                             GURL /* origin */,
                             blink::WebNotificationPermission /* result */)