Remove the OnError method from notification delegates.

ash/system/chromeos/bluetooth/bluetooth_notification_controller.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 "ash/system/chromeos/bluetooth/bluetooth_notification_controller.h"
 
 #include "ash/system/system_notifier.h"
 #include "base/bind.h"
 #include "base/callback.h"
 #include "base/logging.h"
@@ skipping 41 matching lines @@
     : public message_center::NotificationDelegate {
  public:
   BluetoothPairingNotificationDelegate(scoped_refptr<BluetoothAdapter> adapter,
                                        const std::string& address);
 
  protected:
   virtual ~BluetoothPairingNotificationDelegate();
 
   // message_center::NotificationDelegate overrides.
   virtual void Display() override;
-  virtual void Error() override;
   virtual void Close(bool by_user) override;
   virtual bool HasClickedListener() override;
   virtual void Click() override;
   virtual void ButtonClick(int button_index) override;
 
  private:
   // Buttons that appear in notifications.
   enum Button {
     BUTTON_ACCEPT,
     BUTTON_REJECT
@@ skipping 16 matching lines @@
     : adapter_(adapter),
       address_(address) {
 }
 
 BluetoothPairingNotificationDelegate::~BluetoothPairingNotificationDelegate() {
 }
 
 void BluetoothPairingNotificationDelegate::Display() {
 }
 
-void BluetoothPairingNotificationDelegate::Error() {
-}
-
 void BluetoothPairingNotificationDelegate::Close(bool by_user) {
   VLOG(1) << "Pairing notification closed. by_user = " << by_user;
   // Ignore notification closes generated as a result of pairing completion.
   if (!by_user)
     return;
 
   // Cancel the pairing of the device, if the object still exists.
   BluetoothDevice* device = adapter_->GetDevice(address_);
   if (device)
     device->CancelPairing();
@@ skipping 249 matching lines @@
       base::string16() /* display source */,
       message_center::NotifierId(
           message_center::NotifierId::SYSTEM_COMPONENT,
           system_notifier::kNotifierBluetooth),
       optional,
       NULL));
   message_center::MessageCenter::Get()->AddNotification(notification.Pass());
 }
 
 }  // namespace ash