Remove content::NotificationObserver dependency from most Prefs code.

chrome/browser/protector/base_prefs_change.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_BASE_PREFS_CHANGE_H_
 #define CHROME_BROWSER_PROTECTOR_BASE_PREFS_CHANGE_H_
 
 #include <string>
 
 #include "base/memory/scoped_ptr.h"
 #include "base/prefs/public/pref_change_registrar.h"
+#include "base/prefs/public/pref_observer.h"
 #include "chrome/browser/protector/base_setting_change.h"
-#include "content/public/browser/notification_observer.h"
 
 namespace protector {
 
 // BaseSettingChange subclass for PrefService-managed settings changes.
 class BasePrefsChange : public BaseSettingChange,
-                        public content::NotificationObserver {
+                        public PrefObserver {
  public:
   BasePrefsChange();
   virtual ~BasePrefsChange();
 
   // BaseSettingChange overrides:
   virtual bool Init(Profile* profile) OVERRIDE;
   virtual void InitWhenDisabled(Profile* profile) OVERRIDE;
 
  protected:
   // Marks |this| to be dismissed when |pref_name| is changed. Should only be
   // called after Init.
   void DismissOnPrefChange(const std::string& pref_name);
 
   // Ignores any further changes to prefs. No further DismissOnPrefChange calls
   // can be made.
   void IgnorePrefChanges();
 
  private:
-  // content::NotificationObserver overrides:
-  virtual void Observe(int type,
-                       const content::NotificationSource& source,
-                       const content::NotificationDetails& details) OVERRIDE;
+  // PrefObserver overrides:
+  virtual void OnPreferenceChanged(PrefServiceBase* service,
+                                   const std::string& pref_name) OVERRIDE;
 
   PrefChangeRegistrar pref_observer_;
 
   DISALLOW_COPY_AND_ASSIGN(BasePrefsChange);
 };
 
 }  // namespace protector
 
 #endif  // CHROME_BROWSER_PROTECTOR_BASE_PREFS_CHANGE_H_