Revert of Move base/prefs to components/prefs

components/prefs/mock_pref_change_callback.cc

-// Copyright (c) 2011 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.
-
-#include "base/prefs/mock_pref_change_callback.h"
-
-#include "base/bind.h"
-
-MockPrefChangeCallback::MockPrefChangeCallback(PrefService* prefs)
-    : prefs_(prefs) {
-}
-
-MockPrefChangeCallback::~MockPrefChangeCallback() {}
-
-PrefChangeRegistrar::NamedChangeCallback MockPrefChangeCallback::GetCallback() {
-  return base::Bind(&MockPrefChangeCallback::OnPreferenceChanged,
-                    base::Unretained(this));
-}
-
-void MockPrefChangeCallback::Expect(const std::string& pref_name,
-                                    const base::Value* value) {
-  EXPECT_CALL(*this, OnPreferenceChanged(pref_name))
-      .With(PrefValueMatches(prefs_, pref_name, value));
-}