Revert of Delete base/prefs and update callers to use components.

components/prefs/scoped_user_pref_update.h

 // Copyright 2013 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.
 //
 // A helper class that assists preferences in firing notifications when lists
 // or dictionaries are changed.
 
-#ifndef COMPONENTS_PREFS_SCOPED_USER_PREF_UPDATE_H_
-#define COMPONENTS_PREFS_SCOPED_USER_PREF_UPDATE_H_
+#ifndef BASE_PREFS_SCOPED_USER_PREF_UPDATE_H_
+#define BASE_PREFS_SCOPED_USER_PREF_UPDATE_H_
 
 #include <string>
 
 #include "base/macros.h"
 #include "base/threading/non_thread_safe.h"
 #include "base/values.h"
 #include "components/prefs/base_prefs_export.h"
 #include "components/prefs/pref_service.h"
 
 class PrefService;
 
 namespace base {
 class DictionaryValue;
 class ListValue;
 }
 
 namespace subtle {
 
 // Base class for ScopedUserPrefUpdateTemplate that contains the parts
 // that do not depend on ScopedUserPrefUpdateTemplate's template parameter.
 //
 // We need this base class mostly for making it a friend of PrefService
 // and getting access to PrefService::GetMutableUserPref and
 // PrefService::ReportUserPrefChanged.
-class COMPONENTS_PREFS_EXPORT ScopedUserPrefUpdateBase
-    : public base::NonThreadSafe {
+class BASE_PREFS_EXPORT ScopedUserPrefUpdateBase : public base::NonThreadSafe {
  protected:
   ScopedUserPrefUpdateBase(PrefService* service, const std::string& path);
 
   // Calls Notify().
   ~ScopedUserPrefUpdateBase();
 
   // Sets |value_| to |service_|->GetMutableUserPref and returns it.
   base::Value* GetValueOfType(base::Value::Type type);
 
  private:
@@ skipping 53 matching lines @@
  private:
   DISALLOW_COPY_AND_ASSIGN(ScopedUserPrefUpdate);
 };
 
 typedef ScopedUserPrefUpdate<base::DictionaryValue,
                              base::Value::TYPE_DICTIONARY>
     DictionaryPrefUpdate;
 typedef ScopedUserPrefUpdate<base::ListValue, base::Value::TYPE_LIST>
     ListPrefUpdate;
 
-#endif  // COMPONENTS_PREFS_SCOPED_USER_PREF_UPDATE_H_
+#endif  // BASE_PREFS_SCOPED_USER_PREF_UPDATE_H_