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diff --git a/base/prefs/public/pref_change_registrar.h b/base/prefs/public/pref_change_registrar.h
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+++ b/base/prefs/public/pref_change_registrar.h
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+// Copyright (c) 2010 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 BASE_PREFS_PUBLIC_PREF_CHANGE_REGISTRAR_H_
+#define BASE_PREFS_PUBLIC_PREF_CHANGE_REGISTRAR_H_
+
+#include <set>
+#include <string>
+
+#include "base/basictypes.h"
+
+class PrefServiceBase;
+
+namespace content {
+class NotificationObserver;
+}
+
+// Automatically manages the registration of one or more pref change observers
+// with a PrefStore. Functions much like NotificationRegistrar, but specifically
+// manages observers of preference changes. When the Registrar is destroyed,
+// all registered observers are automatically unregistered with the PrefStore.
+class PrefChangeRegistrar {
+ public:
+  PrefChangeRegistrar();
+  virtual ~PrefChangeRegistrar();
+
+  // Must be called before adding or removing observers. Can be called more
+  // than once as long as the value of |service| doesn't change.
+  void Init(PrefServiceBase* service);
+
+  // Adds an pref observer for the specified pref |path| and |obs| observer
+  // object. All registered observers will be automatically unregistered
+  // when the registrar's destructor is called unless the observer has been
+  // explicitly removed by a call to Remove beforehand.
+  void Add(const char* path,
+           content::NotificationObserver* obs);
+
+  // Removes a preference observer that has previously been added with a call to
+  // Add.
+  void Remove(const char* path,
+              content::NotificationObserver* obs);
+
+  // Removes all observers that have been previously added with a call to Add.
+  void RemoveAll();
+
+  // Returns true if no pref observers are registered.
+  bool IsEmpty() const;
+
+  // Check whether |pref| is in the set of preferences being observed.
+  bool IsObserved(const std::string& pref);
+
+  // Check whether any of the observed preferences has the managed bit set.
+  bool IsManaged();
+
+ private:
+  typedef std::pair<std::string, content::NotificationObserver*>
+      ObserverRegistration;
+
+  std::set<ObserverRegistration> observers_;
+  PrefServiceBase* service_;
+
+  DISALLOW_COPY_AND_ASSIGN(PrefChangeRegistrar);
+};
+
+#endif  // BASE_PREFS_PUBLIC_PREF_CHANGE_REGISTRAR_H_