Replace the WAS_INSTALLED_BY_CUSTODIAN creation flag with a pref

extensions/browser/extension_prefs.h

 // Copyright 2014 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 EXTENSIONS_BROWSER_EXTENSION_PREFS_H_
 #define EXTENSIONS_BROWSER_EXTENSION_PREFS_H_
 
 #include <memory>
 #include <set>
 #include <string>
@@ skipping 391 matching lines @@
 
   // Returns true if the user has chosen to allow this extension to inject
   // scripts into pages with file URLs.
   //
   // IMPORTANT: you probably want to use extensions::util::AllowFileAccess
   // instead of this method.
   bool AllowFileAccess(const std::string& extension_id) const;
   void SetAllowFileAccess(const std::string& extension_id, bool allow);
   bool HasAllowFileAccessSetting(const std::string& extension_id) const;
 
+  // Returns true if this extension has been installed by the custodian of
+  // a supervised user.  It is relevant for supervised users and used to block

[Marc Treib, 2016/06/13 12:17:09]

nitty nit: only one space after "."

[mamir, 2016/06/13 14:15:57]

Done.

+  // them from uninstalling the extension for example.
+  bool WasInstalledByCustodian(const std::string& extension_id) const;
+  void SetWasInstalledByCustodian(const std::string& extension_id,
+                                  bool installed_by_custodian);
+
   // Saves ExtensionInfo for each installed extension with the path to the
   // version directory and the location. Blacklisted extensions won't be saved
   // and neither will external extensions the user has explicitly uninstalled.
   // Caller takes ownership of returned structure.
   std::unique_ptr<ExtensionsInfo> GetInstalledExtensionsInfo() const;
 
   // Same as above, but only includes external extensions the user has
   // explicitly uninstalled.
   std::unique_ptr<ExtensionsInfo> GetUninstalledExtensionsInfo() const;
 
@@ skipping 265 matching lines @@
   bool extensions_disabled_;
 
   base::ObserverList<ExtensionPrefsObserver> observer_list_;
 
   DISALLOW_COPY_AND_ASSIGN(ExtensionPrefs);
 };
 
 }  // namespace extensions
 
 #endif  // EXTENSIONS_BROWSER_EXTENSION_PREFS_H_