[Extensions] Un-refcount PermissionSet

extensions/common/extension.h

 // Copyright (c) 2013 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_COMMON_EXTENSION_H_
 #define EXTENSIONS_COMMON_EXTENSION_H_
 
 #include <algorithm>
 #include <iosfwd>
 #include <map>
@@ skipping 556 matching lines @@
   };
 
   Reason reason;
 
   // The extension who's permissions have changed.
   const Extension* extension;
 
   // The permissions that have changed. For Reason::ADDED, this would contain
   // only the permissions that have added, and for Reason::REMOVED, this would
   // only contain the removed permissions.
-  const PermissionSet* permissions;
+  const PermissionSet& permissions;
 
-  UpdatedExtensionPermissionsInfo(
-      const Extension* extension,
-      const PermissionSet* permissions,
-      Reason reason);
+  UpdatedExtensionPermissionsInfo(const Extension* extension,
+                                  const PermissionSet& permissions,
+                                  Reason reason);
 };
 
 }  // namespace extensions
 
 #endif  // EXTENSIONS_COMMON_EXTENSION_H_