Remove the OnError method from notification delegates.

content/browser/notifications/page_notification_delegate.cc

 // 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.
 
 #include "content/browser/notifications/page_notification_delegate.h"
 
 #include "content/browser/notifications/notification_message_filter.h"
 #include "content/browser/renderer_host/render_process_host_impl.h"
 #include "content/common/platform_notification_messages.h"
 #include "content/public/browser/render_process_host.h"
 
 namespace content {
 
 PageNotificationDelegate::PageNotificationDelegate(int render_process_id,
                                                    int notification_id)
     : render_process_id_(render_process_id),
       notification_id_(notification_id) {}
 
 PageNotificationDelegate::~PageNotificationDelegate() {}
 
 void PageNotificationDelegate::NotificationDisplayed() {
   RenderProcessHost* sender = RenderProcessHost::FromID(render_process_id_);
   if (!sender)
     return;
 
   sender->Send(new PlatformNotificationMsg_DidShow(notification_id_));
 }
 
-void PageNotificationDelegate::NotificationError() {
-  RenderProcessHost* sender = RenderProcessHost::FromID(render_process_id_);
-  if (!sender)
-    return;
-
-  sender->Send(new PlatformNotificationMsg_DidError(notification_id_));
-}
-
 // TODO(peter): Remove |by_user| since we're not using that anywhere.
 void PageNotificationDelegate::NotificationClosed(bool by_user) {
   RenderProcessHost* sender = RenderProcessHost::FromID(render_process_id_);
   if (!sender)
     return;
 
   sender->Send(new PlatformNotificationMsg_DidClose(notification_id_));
   static_cast<RenderProcessHostImpl*>(sender)
       ->notification_message_filter()->DidCloseNotification(notification_id_);
 }
 
 void PageNotificationDelegate::NotificationClick() {
   RenderProcessHost* sender = RenderProcessHost::FromID(render_process_id_);
   if (!sender)
     return;
 
   sender->Send(new PlatformNotificationMsg_DidClick(notification_id_));
 }
 
 }  // namespace content