Update from https://crrev.com/309415

base/prefs/pref_service.h

 // 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.
 
 // This provides a way to access the application's current preferences.
 
 // Chromium settings and storage represent user-selected preferences and
 // information and MUST not be extracted, overwritten or modified except
 // through Chromium defined APIs.
 
@@ skipping 70 matching lines @@
     const base::Value* GetValue() const;
 
     // Returns the value recommended by the admin, if any.
     const base::Value* GetRecommendedValue() const;
 
     // Returns true if the Preference is managed, i.e. set by an admin policy.
     // Since managed prefs have the highest priority, this also indicates
     // whether the pref is actually being controlled by the policy setting.
     bool IsManaged() const;
 
+    // Returns true if the Preference is controlled by the custodian of the
+    // supervised user. Since a supervised user is not expected to have an admin
+    // policy, this is the controlling pref if set.
+    bool IsManagedByCustodian() const;
+
     // Returns true if the Preference is recommended, i.e. set by an admin
     // policy but the user is allowed to change it.
     bool IsRecommended() const;
 
     // Returns true if the Preference has a value set by an extension, even if
     // that value is being overridden by a higher-priority source.
     bool HasExtensionSetting() const;
 
     // Returns true if the Preference has a user setting, even if that value is
     // being overridden by a higher-priority source.
@@ skipping 50 matching lines @@
   virtual ~PrefService();
 
   // Lands pending writes to disk. This should only be used if we need to save
   // immediately (basically, during shutdown).
   void CommitPendingWrite();
 
   // Returns true if the preference for the given preference name is available
   // and is managed.
   bool IsManagedPreference(const std::string& pref_name) const;
 
+  // Returns true if the preference for the given preference name is available
+  // and is controlled by the parent/guardian of the child Account.
+  bool IsPreferenceManagedByCustodian(const std::string& pref_name) const;
+
   // Returns |true| if a preference with the given name is available and its
   // value can be changed by the user.
   bool IsUserModifiablePreference(const std::string& pref_name) const;
 
   // Look up a preference.  Returns NULL if the preference is not
   // registered.
   const PrefService::Preference* FindPreference(const std::string& path) const;
 
   // If the path is valid and the value at the end of the path matches the type
   // specified, it will return the specified value.  Otherwise, the default
@@ skipping 180 matching lines @@
 
   // Local cache of registered Preference objects. The pref_registry_
   // is authoritative with respect to what the types and default values
   // of registered preferences are.
   mutable PreferenceMap prefs_map_;
 
   DISALLOW_COPY_AND_ASSIGN(PrefService);
 };
 
 #endif  // BASE_PREFS_PREF_SERVICE_H_