Introduce incognito preference settings.

chrome/browser/prefs/overlay_persistent_pref_store.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 "chrome/browser/prefs/overlay_persistent_pref_store.h"
+
+OverlayPersistentPrefStore::OverlayPersistentPrefStore(
+    PersistentPrefStore* underlay)
+    : underlay_(underlay) {
+  underlay_->AddObserver(this);
+}
+OverlayPersistentPrefStore::~OverlayPersistentPrefStore() {
+  underlay_->RemoveObserver(this);
+}
+
+void OverlayPersistentPrefStore::AddObserver(PrefStore::Observer* observer) {
+  observers_.AddObserver(observer);
+}
+
+void OverlayPersistentPrefStore::RemoveObserver(PrefStore::Observer* observer) {
+  observers_.RemoveObserver(observer);
+}
+
+bool OverlayPersistentPrefStore::IsInitializationComplete() const {
+  return underlay_->IsInitializationComplete();
+}
+
+PrefStore::ReadResult OverlayPersistentPrefStore::GetValue(
+    const std::string& key, Value** result) const {
+  if (overlay_.GetValue(key, result))
+    return READ_OK;
+  return underlay_->GetValue(key, result);
+}
+
+void OverlayPersistentPrefStore::SetValue(const std::string& key,
+                                          Value* value) {
+  if (overlay_.SetValue(key, value))
+    FOR_EACH_OBSERVER(PrefStore::Observer, observers_, OnPrefValueChanged(key));
+}
+
+void OverlayPersistentPrefStore::SetValueSilently(const std::string& key,
+                                                  Value* value) {
+  overlay_.SetValue(key, value);
+}
+
+void OverlayPersistentPrefStore::RemoveValue(const std::string& key) {
+  if (overlay_.RemoveValue(key))
+    FOR_EACH_OBSERVER(PrefStore::Observer, observers_, OnPrefValueChanged(key));
+}
+
+bool OverlayPersistentPrefStore::ReadOnly() const {
+  return false;
+}
+
+PersistentPrefStore::PrefReadError OverlayPersistentPrefStore::ReadPrefs() {
+  // We do not read intentionally.
+  return PersistentPrefStore::PREF_READ_ERROR_NONE;
+}
+
+bool OverlayPersistentPrefStore::WritePrefs() {
+  // We do not write intentionally.
+  return true;
+}
+
+void OverlayPersistentPrefStore::ScheduleWritePrefs() {
+  // We do not write intentionally.
+}
+
+void OverlayPersistentPrefStore::OnPrefValueChanged(const std::string& key) {
+  if (!overlay_.GetValue(key, NULL))
+    FOR_EACH_OBSERVER(PrefStore::Observer, observers_, OnPrefValueChanged(key));
+}
+
+void OverlayPersistentPrefStore::OnInitializationCompleted() {
+  FOR_EACH_OBSERVER(PrefStore::Observer, observers_,
+                    OnInitializationCompleted());
+}