Fixed regression: various preferences were not persisted when changed from incognito window

chrome/browser/prefs/incognito_user_pref_store.cc

Index: chrome/browser/prefs/incognito_user_pref_store.cc
diff --git a/chrome/browser/prefs/incognito_user_pref_store.cc b/chrome/browser/prefs/incognito_user_pref_store.cc
new file mode 100644
index 0000000000000000000000000000000000000000..87bcb2c8870cbd6f2d2c94c5712b3a04e7dec84b
--- /dev/null
+++ b/chrome/browser/prefs/incognito_user_pref_store.cc
@@ -0,0 +1,152 @@
+// 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/incognito_user_pref_store.h"
+
+#include "base/memory/scoped_ptr.h"
+#include "base/values.h"
+#include "chrome/common/pref_names.h"
+
+IncognitoUserPrefStore::IncognitoUserPrefStore(
+    PersistentPrefStore* underlay)
+    : underlay_(underlay) {
+  underlay_->AddObserver(this);
+}
+
+IncognitoUserPrefStore::~IncognitoUserPrefStore() {
+  underlay_->RemoveObserver(this);
+}
+
+bool IncognitoUserPrefStore::IsSetInOverlay(const std::string& key) const {
+  return overlay_.GetValue(key, NULL);
+}
+
+void IncognitoUserPrefStore::AddObserver(PrefStore::Observer* observer) {
+  observers_.AddObserver(observer);
+}
+
+void IncognitoUserPrefStore::RemoveObserver(PrefStore::Observer* observer) {
+  observers_.RemoveObserver(observer);
+}
+
+bool IncognitoUserPrefStore::IsInitializationComplete() const {
+  return underlay_->IsInitializationComplete();
+}
+
+PrefStore::ReadResult IncognitoUserPrefStore::GetValue(
+    const std::string& key,
+    const Value** result) const {
+  // If the |key| shall NOT be stored in the overlay store, there must not
+  // be an entry.
+  DCHECK(ShallBeStoredInOverlay(key) || !overlay_.GetValue(key, NULL));
+
+  if (overlay_.GetValue(key, result))
+    return READ_OK;
+  return underlay_->GetValue(key, result);
+}
+
+PrefStore::ReadResult IncognitoUserPrefStore::GetMutableValue(
+    const std::string& key,
+    Value** result) {
+  if (!ShallBeStoredInOverlay(key))
+    return underlay_->GetMutableValue(key, result);
+
+  if (overlay_.GetValue(key, result))
+    return READ_OK;
+
+  // Try to create copy of underlay if the overlay does not contain a value.
+  Value* underlay_value = NULL;
+  PrefStore::ReadResult read_result =
+      underlay_->GetMutableValue(key, &underlay_value);
+  if (read_result != READ_OK)
+    return read_result;
+
+  *result = underlay_value->DeepCopy();
+  overlay_.SetValue(key, *result);
+  return READ_OK;
+}
+
+void IncognitoUserPrefStore::SetValue(const std::string& key,
+                                      Value* value) {
+  if (!ShallBeStoredInOverlay(key)) {
+    underlay_->SetValue(key, value);
+    return;
+  }
+
+  if (overlay_.SetValue(key, value))
+    ReportValueChanged(key);
+}
+
+void IncognitoUserPrefStore::SetValueSilently(const std::string& key,
+                                              Value* value) {
+  if (!ShallBeStoredInOverlay(key)) {
+    underlay_->SetValueSilently(key, value);
+    return;
+  }
+
+  overlay_.SetValue(key, value);
+}
+
+void IncognitoUserPrefStore::RemoveValue(const std::string& key) {
+  if (!ShallBeStoredInOverlay(key)) {
+    underlay_->RemoveValue(key);
+    return;
+  }
+
+  if (overlay_.RemoveValue(key))
+    ReportValueChanged(key);
+}
+
+bool IncognitoUserPrefStore::ReadOnly() const {
+  return false;
+}
+
+PersistentPrefStore::PrefReadError IncognitoUserPrefStore::ReadPrefs() {
+  // We do not read intentionally.
+  OnInitializationCompleted(true);
+  return PersistentPrefStore::PREF_READ_ERROR_NONE;
+}
+
+void IncognitoUserPrefStore::ReadPrefsAsync(
+    ReadErrorDelegate* error_delegate_raw) {
+  scoped_ptr<ReadErrorDelegate> error_delegate(error_delegate_raw);
+  // We do not read intentionally.
+  OnInitializationCompleted(true);
+}
+
+bool IncognitoUserPrefStore::WritePrefs() {
+  // We do not write our content intentionally.
+  return true;
+}
+
+void IncognitoUserPrefStore::ScheduleWritePrefs() {
+  underlay_->ScheduleWritePrefs();
+  // We do not write our content intentionally.
+}
+
+void IncognitoUserPrefStore::CommitPendingWrite() {
+  underlay_->CommitPendingWrite();
+  // We do not write our content intentionally.
+}
+
+void IncognitoUserPrefStore::ReportValueChanged(const std::string& key) {
+  FOR_EACH_OBSERVER(PrefStore::Observer, observers_, OnPrefValueChanged(key));
+}
+
+void IncognitoUserPrefStore::OnPrefValueChanged(const std::string& key) {
+  if (!overlay_.GetValue(key, NULL))
+    ReportValueChanged(key);
+}
+
+void IncognitoUserPrefStore::OnInitializationCompleted(bool succeeded) {
+  FOR_EACH_OBSERVER(PrefStore::Observer, observers_,
+                    OnInitializationCompleted(succeeded));
+}
+
+bool IncognitoUserPrefStore::ShallBeStoredInOverlay(
+    const std::string& key) const {
+  // List of keys that cannot be changed in the user prefs file by the incognito
+  // profile:
+  return key == prefs::kBrowserWindowPlacement;
+}