Remove the OnError method from notification delegates.

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 "content/public/common/show_desktop_notification_params.h"
 #include "ipc/ipc_message_macros.h"
 #include "third_party/WebKit/public/platform/WebNotificationPermission.h"
 #include "url/gurl.h"
 
 #define IPC_MESSAGE_START PlatformNotificationMsgStart
 
 IPC_ENUM_TRAITS_MAX_VALUE(blink::WebNotificationPermission,
                           blink::WebNotificationPermissionLast)
 
 // Messages sent from the browser to the renderer.
 
 // Informs the renderer that the permission request for |request_id| is done,
 // and has been settled with |result|.
 IPC_MESSAGE_ROUTED2(PlatformNotificationMsg_PermissionRequestComplete,
                     int /* request_id */,
                     blink::WebNotificationPermission /* result */)
 
 // Informs the renderer that the browser has displayed the notification.
 IPC_MESSAGE_CONTROL1(PlatformNotificationMsg_DidShow,
                      int /* notification_id */)
 
-// Informs the renderer that the notification could not be displayed.
-IPC_MESSAGE_CONTROL1(PlatformNotificationMsg_DidError,
-                     int /* notification_id */)
-
 // Informs the renderer that the notification has been closed.
 IPC_MESSAGE_CONTROL1(PlatformNotificationMsg_DidClose,
                      int /* notification_id */)
 
 // Informs the renderer that the notification has been clicked on.
 IPC_MESSAGE_CONTROL1(PlatformNotificationMsg_DidClick,
                      int /* notification_id */)
 
 // Messages sent from the renderer to the browser.
 
 // Requests permission to display platform notifications for |origin|.
 IPC_MESSAGE_ROUTED2(PlatformNotificationHostMsg_RequestPermission,
                     GURL /* origin */,
                     int /* request_id */)
 
 IPC_MESSAGE_CONTROL2(PlatformNotificationHostMsg_Show,
                      int /* notification_id */,
                      content::ShowDesktopNotificationHostMsgParams /* params */)
 
 IPC_MESSAGE_CONTROL1(PlatformNotificationHostMsg_Close,
                      int /* notification_id */)
 
 IPC_SYNC_MESSAGE_CONTROL1_1(PlatformNotificationHostMsg_CheckPermission,
                             GURL /* origin */,
                             blink::WebNotificationPermission /* result */)