Revert of Move base/prefs to components/prefs

base/prefs/default_pref_store.cc

+// 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.
+
+#include "base/prefs/default_pref_store.h"
+
+#include <utility>
+
+#include "base/logging.h"
+
+using base::Value;
+
+DefaultPrefStore::DefaultPrefStore() {}
+
+bool DefaultPrefStore::GetValue(const std::string& key,
+                                const Value** result) const {
+  return prefs_.GetValue(key, result);
+}
+
+void DefaultPrefStore::AddObserver(PrefStore::Observer* observer) {
+  observers_.AddObserver(observer);
+}
+
+void DefaultPrefStore::RemoveObserver(PrefStore::Observer* observer) {
+  observers_.RemoveObserver(observer);
+}
+
+bool DefaultPrefStore::HasObservers() const {
+  return observers_.might_have_observers();
+}
+
+void DefaultPrefStore::SetDefaultValue(const std::string& key,
+                                       scoped_ptr<Value> value) {
+  DCHECK(!GetValue(key, NULL));
+  prefs_.SetValue(key, std::move(value));
+}
+
+void DefaultPrefStore::ReplaceDefaultValue(const std::string& key,
+                                           scoped_ptr<Value> value) {
+  const Value* old_value = NULL;
+  GetValue(key, &old_value);
+  bool notify = !old_value->Equals(value.get());
+  prefs_.SetValue(key, std::move(value));
+  if (notify)
+    FOR_EACH_OBSERVER(Observer, observers_, OnPrefValueChanged(key));
+}
+
+DefaultPrefStore::const_iterator DefaultPrefStore::begin() const {
+  return prefs_.begin();
+}
+
+DefaultPrefStore::const_iterator DefaultPrefStore::end() const {
+  return prefs_.end();
+}
+
+DefaultPrefStore::~DefaultPrefStore() {}