md-settings: Added settings for fingerprint 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/pref_registry/pref_registry_syncable.h"
 #include "components/prefs/pref_registry_simple.h"
 #include "components/prefs/pref_service.h"
 #include "components/user_manager/user_manager.h"
 
 namespace chromeos {
 
 namespace {
 bool enable_for_testing_ = false;
 // Options for the quick unlock whitelist.
 const char kQuickUnlockWhitelistOptionAll[] = "all";
 const char kQuickUnlockWhitelistOptionPin[] = "PIN";
 }  // namespace
 
 void RegisterQuickUnlockProfilePrefs(PrefRegistrySimple* registry) {
   base::ListValue quick_unlock_whitelist_default;
   quick_unlock_whitelist_default.AppendString(kQuickUnlockWhitelistOptionPin);
   registry->RegisterListPref(prefs::kQuickUnlockModeWhitelist,
                              quick_unlock_whitelist_default.DeepCopy());
   registry->RegisterIntegerPref(
       prefs::kQuickUnlockTimeout,
       static_cast<int>(QuickUnlockPasswordConfirmationFrequency::DAY));
+  registry->RegisterBooleanPref(
+      prefs::kEnableQuickUnlockFingerprint, false,

[jdufault, 2016/12/01 17:11:19]

I believe the pref is syncable by default, so this flag is not needed (also drop
the include).

[sammiequon, 2016/12/01 20:52:28]

Done.

+      user_prefs::PrefRegistrySyncable::SYNCABLE_PREF);
 }
 
 bool IsPinUnlockEnabled(PrefService* pref_service) {
   if (enable_for_testing_)
     return true;
 
   // Check if policy allows PIN.
   const base::ListValue* quick_unlock_whitelist =
       pref_service->GetList(prefs::kQuickUnlockModeWhitelist);
   base::StringValue all_value(kQuickUnlockWhitelistOptionAll);
   base::StringValue pin_value(kQuickUnlockWhitelistOptionPin);
   if (quick_unlock_whitelist->Find(all_value) ==
           quick_unlock_whitelist->end() &&
       quick_unlock_whitelist->Find(pin_value) ==
           quick_unlock_whitelist->end()) {
     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 IsFingerprintUnlockEnabled() {
+  // Enable fingerprint unlock only if the switch is present. For now,
+  // fingerprint unlock will not be seen if quick unlock switch is not present,
+  // so check that too.
+  return base::FeatureList::IsEnabled(features::kQuickUnlockPin) &&

[jdufault, 2016/12/01 17:11:19]

Why are these tied together like this?

[sammiequon, 2016/12/01 20:52:29]

The fingerprint settings are under the lock screen so we cannot set it up
without kQuickUnlockPin enabled so it is not usuable with kQuickUnlockPin turned
off.

[jdufault, 2016/12/02 23:02:11]

You should update the comment with that info.

[sammiequon, 2016/12/03 21:40:51]

Done.

+         base::FeatureList::IsEnabled(features::kQuickUnlockFingerprint);
+}
+
 void EnableQuickUnlockForTesting() {
   enable_for_testing_ = true;
 }
 
 }  // namespace chromeos