Remove PrefObserver usage, batch 3.

chrome/browser/chromeos/preferences.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_CHROMEOS_PREFERENCES_H_
 #define CHROME_BROWSER_CHROMEOS_PREFERENCES_H_
 
 #include <string>
 #include <vector>
 
 #include "base/compiler_specific.h"
-#include "base/prefs/public/pref_observer.h"
 #include "chrome/browser/api/prefs/pref_member.h"
 #include "chrome/browser/chromeos/language_preferences.h"
 
 class PrefService;
 
 namespace chromeos {
 namespace input_method {
 class InputMethodManager;
 }  // namespace input_method
 
 // The Preferences class handles Chrome OS preferences. When the class
 // is first initialized, it will initialize the OS settings to what's stored in
 // the preferences. These include touchpad settings, etc.
 // When the preferences change, we change the settings to reflect the new value.
-class Preferences : public PrefObserver {
+class Preferences {
  public:
   Preferences();
   explicit Preferences(
       input_method::InputMethodManager* input_method_manager);  // for testing
   virtual ~Preferences();
 
   // This method will register the prefs associated with Chrome OS settings.
   static void RegisterUserPrefs(PrefService* prefs);
 
   // This method will initialize Chrome OS settings to values in user prefs.
   void Init(PrefService* prefs);
 
-  // Overridden from PrefObserver:
-  virtual void OnPreferenceChanged(PrefServiceBase* service,
-                                   const std::string& pref_name) OVERRIDE;
-
   void InitUserPrefsForTesting(PrefService* prefs);
   void SetInputMethodListForTesting();
 
  private:
   // Initializes all member prefs.
   void InitUserPrefs(PrefService* prefs);
 
+  // Callback method for preference changes.
+  void OnPreferenceChanged(const std::string& pref_name);
+
   // This will set the OS settings when the preference changes.
   // If this method is called with NULL, it will set all OS settings to what's
   // stored in the preferences.
   void NotifyPrefChanged(const std::string* pref_name);
 
   // Writes boolean |value| to the input method (IBus) configuration daemon.
   // |section| (e.g. "general") and |name| (e.g. "use_global_engine") should
   // not be NULL.
   void SetLanguageConfigBoolean(const char* section,
                                 const char* name,
@@ skipping 87 matching lines @@
   BooleanPrefMember enable_screen_lock_;
 
   BooleanPrefMember enable_drm_;
 
   DISALLOW_COPY_AND_ASSIGN(Preferences);
 };
 
 }  // namespace chromeos
 
 #endif  // CHROME_BROWSER_CHROMEOS_PREFERENCES_H_