cros: Added policies for screen unlock.

chrome/browser/chromeos/login/quick_unlock/quick_unlock_utils.cc

 // Copyright 2016 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/login/quick_unlock/quick_unlock_utils.h"
 
 #include "base/feature_list.h"
 #include "chrome/browser/browser_process.h"
 #include "chrome/browser/chromeos/policy/browser_policy_connector_chromeos.h"
 #include "chrome/common/chrome_features.h"
+#include "chrome/common/pref_names.h"
+#include "components/prefs/pref_service.h"
 #include "components/user_manager/user_manager.h"
 
 namespace chromeos {
 
 namespace {
 bool enable_for_testing_ = false;
 }  // namespace
 
-bool IsQuickUnlockEnabled() {
+bool IsQuickUnlockEnabled(PrefService* pref_service) {
   if (enable_for_testing_)
     return true;
 
-  // TODO(jdufault): Implement a proper policy check. For now, just disable if
-  // the device is enterprise enrolled. See crbug.com/612271.
-  if (g_browser_process->platform_part()
-          ->browser_policy_connector_chromeos()
-          ->IsEnterpriseManaged()) {
+  // Check if policy allows PIN.
+  if (!IsPinUnlockEnabled(pref_service))
     return false;
-  }
 
   // TODO(jdufault): Disable PIN for supervised users until we allow the owner
   // to set the PIN. See crbug.com/632797.
   user_manager::User* user = user_manager::UserManager::Get()->GetActiveUser();
   if (user && user->IsSupervised())
     return false;
 
   // Enable quick unlock only if the switch is present.
   return base::FeatureList::IsEnabled(features::kQuickUnlockPin);
 }
 
+bool IsPinUnlockEnabled(PrefService* pref_service) {
+  const base::ListValue* screen_lock_whitelist =
+      pref_service->GetList(prefs::kQuickUnlockModeWhitelist);
+  base::StringValue all_value("all");
+  base::StringValue pin_value("pin");
+  return screen_lock_whitelist->Find(all_value) !=
+             screen_lock_whitelist->end() ||
+         screen_lock_whitelist->Find(pin_value) != screen_lock_whitelist->end();
+}
+
 void EnableQuickUnlockForTesting() {
   enable_for_testing_ = true;
 }
 
 }  // namespace chromeos