Add the restore preference for the full restore feature.

This CL adds the "settings.restore_apps_and_pages" preference item to
prepare for the full restore feature.
DD: go/chrome-os-full-restore-dd

BUG=1146900

Change-Id: I259cc7fac01e77407337dbc2942ef645191c6057
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2533213
Commit-Queue: Nancy Wang <nancylingwang@chromium.org>
Reviewed-by: Dominic Battré <battre@chromium.org>
Reviewed-by: Kyle Horimoto <khorimoto@chromium.org>
Cr-Commit-Position: refs/heads/master@{#826594}

chrome/browser/chromeos/BUILD.gn

@@ -1411,6 +1411,8 @@ source_set("chromeos") {
     "first_run/steps/app_list_step.h",
     "first_run/steps/tray_step.cc",
     "first_run/steps/tray_step.h",
+    "full_restore/full_restore_prefs.cc",
+    "full_restore/full_restore_prefs.h",
     "guest_os/guest_os_external_protocol_handler.cc",
     "guest_os/guest_os_external_protocol_handler.h",
     "guest_os/guest_os_pref_names.cc",

chrome/browser/chromeos/full_restore/full_restore_prefs.cc

+// Copyright 2020 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/chromeos/full_restore/full_restore_prefs.h"
+
+#include "ash/public/cpp/ash_features.h"
+#include "components/pref_registry/pref_registry_syncable.h"
+#include "components/prefs/pref_registry_simple.h"
+
+namespace chromeos {
+namespace full_restore {
+
+// An integer pref to define whether restore apps and web pages on startup.
+// Refer to |RestoreOption|.
+const char kRestoreAppsAndPagesPrefName[] = "settings.restore_apps_and_pages";
+
+// TODO(https://crbug.com/1131969): Add the restore user preference init, and
+// modificaiton implementation.
+
+void RegisterProfilePrefs(PrefRegistrySimple* registry) {
+  if (ash::features::IsFullRestoreEnabled()) {
+    registry->RegisterIntegerPref(
+        kRestoreAppsAndPagesPrefName, static_cast<int>(RestoreOption::kAlways),
+        user_prefs::PrefRegistrySyncable::SYNCABLE_OS_PREF);
+  }
+}
+
+}  // namespace full_restore
+}  // namespace chromeos

chrome/browser/chromeos/full_restore/full_restore_prefs.h

+// Copyright 2020 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.
+
+#ifndef CHROME_BROWSER_CHROMEOS_FULL_RESTORE_FULL_RESTORE_PREFS_H_
+#define CHROME_BROWSER_CHROMEOS_FULL_RESTORE_FULL_RESTORE_PREFS_H_
+
+class PrefRegistrySimple;
+
+namespace chromeos {
+namespace full_restore {
+
+// Enum that specifies restore options on startup. The values must not be
+// changed as they are persisted on disk.
+enum class RestoreOption {
+  kAlways = 1,
+  kAskEveryTime = 2,
+  kDoNotRestore = 3,
+};
+
+extern const char kRestoreAppsAndPagesPrefName[];
+
+void RegisterProfilePrefs(PrefRegistrySimple* registry);
+
+}  // namespace full_restore
+}  // namespace chromeos
+
+#endif  // CHROME_BROWSER_CHROMEOS_FULL_RESTORE_FULL_RESTORE_PREFS_H_

chrome/browser/extensions/api/settings_private/prefs_util.cc

@@ -53,6 +53,7 @@
 #include "ash/public/cpp/ambient/ambient_prefs.h"
 #include "ash/public/cpp/ash_pref_names.h"  // nogncheck
 #include "chrome/browser/chromeos/crostini/crostini_pref_names.h"
+#include "chrome/browser/chromeos/full_restore/full_restore_prefs.h"
 #include "chrome/browser/chromeos/guest_os/guest_os_pref_names.h"
 #include "chrome/browser/chromeos/ownership/owner_settings_service_chromeos.h"
 #include "chrome/browser/chromeos/ownership/owner_settings_service_chromeos_factory.h"
@@ -593,6 +594,10 @@ const PrefsUtil::TypedPrefMap& PrefsUtil::GetAllowlistedKeys() {
   (*s_allowlist)[arc::prefs::kAlwaysOnVpnLockdown] =
       settings_api::PrefType::PREF_TYPE_BOOLEAN;
 
+  // Restore apps and pages on startup
+  (*s_allowlist)[chromeos::full_restore::kRestoreAppsAndPagesPrefName] =
+      settings_api::PrefType::PREF_TYPE_NUMBER;
+
   // Timezone settings.
   (*s_allowlist)[chromeos::kSystemTimezone] =
       settings_api::PrefType::PREF_TYPE_STRING;

chrome/browser/prefs/browser_prefs.cc

@@ -276,6 +276,7 @@
 #include "chrome/browser/chromeos/child_accounts/secondary_account_consent_logger.h"
 #include "chrome/browser/chromeos/file_system_provider/registry.h"
 #include "chrome/browser/chromeos/first_run/first_run.h"
+#include "chrome/browser/chromeos/full_restore/full_restore_prefs.h"
 #include "chrome/browser/chromeos/guest_os/guest_os_pref_names.h"
 #include "chrome/browser/chromeos/lock_screen_apps/state_controller.h"
 #include "chrome/browser/chromeos/login/demo_mode/demo_mode_detector.h"
@@ -944,6 +945,7 @@ void RegisterProfilePrefs(user_prefs::PrefRegistrySyncable* registry,
   chromeos::FamilyUserSessionMetrics::RegisterProfilePrefs(registry);
   chromeos::first_run::RegisterProfilePrefs(registry);
   chromeos::file_system_provider::RegisterProfilePrefs(registry);
+  chromeos::full_restore::RegisterProfilePrefs(registry);
   chromeos::KerberosCredentialsManager::RegisterProfilePrefs(registry);
   chromeos::login::SecurityTokenSessionController::RegisterPrefs(registry);
   chromeos::multidevice_setup::MultiDeviceSetupService::RegisterProfilePrefs(