cros: Added policies for screen unlock.

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

 // 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.
 
 #ifndef CHROME_BROWSER_CHROMEOS_LOGIN_QUICK_UNLOCK_QUICK_UNLOCK_UTILS_H_
 #define CHROME_BROWSER_CHROMEOS_LOGIN_QUICK_UNLOCK_QUICK_UNLOCK_UTILS_H_
 
+class PrefRegistrySimple;
+class PrefService;
+
 namespace chromeos {
 
-// Returns true if quick unlock is allowed by policy and the feature flag is
-// present.
-bool IsQuickUnlockEnabled();
+// Enumeration specifiying the possible intervals before a strong auth
+// (password) is required to use quick unlock. These values correspond to the
+// policy items of QuickUnlockTimeout (policy ID 352) in policy_templates.json,
+// and should be updated accordingly.
+enum class QuickUnlockPasswordConfirmationFrequency {
+  SIX_HOURS = 0,
+  TWELVE_HOURS = 1,
+  DAY = 2,
+  WEEK = 3
+};
+
+// Register quick unlock prefs.
+void RegisterQuickUnlockProfilePrefs(PrefRegistrySimple* registry);
+
+// Returns true if PIN unlock is allowed by policy and the quick unlock feature
+// flag is present.
+bool IsPinUnlockEnabled(PrefService* pref_service);
 
 // Forcibly enable quick-unlock for testing.
 void EnableQuickUnlockForTesting();
 
 }  // namespace chromeos
 
 #endif  // CHROME_BROWSER_CHROMEOS_LOGIN_QUICK_UNLOCK_QUICK_UNLOCK_UTILS_H_