Update from https://crrev.com/309415

base/prefs/pref_value_store.cc

 // Copyright (c) 2012 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 "base/prefs/pref_value_store.h"
 
 #include "base/logging.h"
 #include "base/prefs/pref_notifier.h"
 #include "base/prefs/pref_observer.h"
 
@@ skipping 120 matching lines @@
   // effective value of the pref will not have changed.
   pref_notifier_->OnPreferenceChanged(path);
   if (!pref_changed_callback_.is_null())
     pref_changed_callback_.Run(path);
 }
 
 bool PrefValueStore::PrefValueInManagedStore(const std::string& name) const {
   return PrefValueInStore(name, MANAGED_STORE);
 }
 
+bool PrefValueStore::PrefValueInSupervisedStore(const std::string& name) const {
+  return PrefValueInStore(name, SUPERVISED_USER_STORE);
+}
+
 bool PrefValueStore::PrefValueInExtensionStore(const std::string& name) const {
   return PrefValueInStore(name, EXTENSION_STORE);
 }
 
 bool PrefValueStore::PrefValueInUserStore(const std::string& name) const {
   return PrefValueInStore(name, USER_STORE);
 }
 
 bool PrefValueStore::PrefValueFromExtensionStore(
     const std::string& name) const {
@@ skipping 124 matching lines @@
   if (initialization_failed_)
     return;
   for (size_t i = 0; i <= PREF_STORE_TYPE_MAX; ++i) {
     scoped_refptr<PrefStore> store =
         GetPrefStore(static_cast<PrefStoreType>(i));
     if (store.get() && !store->IsInitializationComplete())
       return;
   }
   pref_notifier_->OnInitializationCompleted(true);
 }