Remove the OnError method from notification delegates.

ash/display/resolution_notification_controller.cc

 // Copyright 2013 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 "ash/display/resolution_notification_controller.h"
 
 #include "ash/display/display_controller.h"
 #include "ash/display/display_info.h"
 #include "ash/display/display_manager.h"
 #include "ash/shell.h"
@@ skipping 23 matching lines @@
   ResolutionChangeNotificationDelegate(
       ResolutionNotificationController* controller,
       bool has_timeout);
 
  protected:
   virtual ~ResolutionChangeNotificationDelegate();
 
  private:
   // message_center::NotificationDelegate overrides:
   virtual void Display() override;
-  virtual void Error() override;
   virtual void Close(bool by_user) override;
   virtual void Click() override;
   virtual bool HasClickedListener() override;
   virtual void ButtonClick(int button_index) override;
 
   ResolutionNotificationController* controller_;
   bool has_timeout_;
 
   DISALLOW_COPY_AND_ASSIGN(ResolutionChangeNotificationDelegate);
 };
 
 ResolutionChangeNotificationDelegate::ResolutionChangeNotificationDelegate(
     ResolutionNotificationController* controller,
     bool has_timeout)
     : controller_(controller),
       has_timeout_(has_timeout) {
   DCHECK(controller_);
 }
 
 ResolutionChangeNotificationDelegate::~ResolutionChangeNotificationDelegate() {
 }
 
 void ResolutionChangeNotificationDelegate::Display() {
 }
 
-void ResolutionChangeNotificationDelegate::Error() {
-}
-
 void ResolutionChangeNotificationDelegate::Close(bool by_user) {
   if (by_user)
     controller_->AcceptResolutionChange(false);
 }
 
 void ResolutionChangeNotificationDelegate::Click() {
   controller_->AcceptResolutionChange(true);
 }
 
 bool ResolutionChangeNotificationDelegate::HasClickedListener() {
@@ skipping 226 matching lines @@
                               this,
                               &ResolutionNotificationController::OnTimerTick);
   }
 }
 
 void ResolutionNotificationController::SuppressTimerForTest() {
   g_use_timer = false;
 }
 
 }  // namespace ash