ProtectorService supports multiple change instances.

chrome/browser/protector/settings_change_global_error_delegate.h

 // Copyright (c) 2012 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.
 
 #ifndef CHROME_BROWSER_PROTECTOR_SETTINGS_CHANGE_GLOBAL_ERROR_DELEGATE_H_
 #define CHROME_BROWSER_PROTECTOR_SETTINGS_CHANGE_GLOBAL_ERROR_DELEGATE_H_
 #pragma once
 
 #include "base/basictypes.h"
 
 class Browser;
 
 namespace protector {
 
+class SettingsChangeGlobalError;
+
 // Interface for notifications about settings change error bubble closing.
 class SettingsChangeGlobalErrorDelegate {
  public:
   virtual ~SettingsChangeGlobalErrorDelegate() {}
 
   // Called if user clicks "Apply change" button.
-  virtual void OnApplyChange(Browser* browser) = 0;
+  virtual void OnApplyChange(SettingsChangeGlobalError* error,
+                             Browser* browser) = 0;
 
   // Called if user clicks "Discard change" button.
-  virtual void OnDiscardChange(Browser* browser) = 0;
+  virtual void OnDiscardChange(SettingsChangeGlobalError* error,
+                               Browser* browser) = 0;
 
   // Called if user clicked outside the bubble and timeout for its reshow
   // has passed.
-  virtual void OnDecisionTimeout() = 0;
+  virtual void OnDecisionTimeout(SettingsChangeGlobalError* error) = 0;
 
   // Called when error is removed from profile so it's safe to delete it.
-  virtual void OnRemovedFromProfile() = 0;
+  virtual void OnRemovedFromProfile(SettingsChangeGlobalError* error) = 0;
 };
 
 }  // namespace protector
 
 #endif  // CHROME_BROWSER_PROTECTOR_SETTINGS_CHANGE_GLOBAL_ERROR_DELEGATE_H_