[Extensions] Un-refcount PermissionSet

extensions/common/extension.h

Index: extensions/common/extension.h
diff --git a/extensions/common/extension.h b/extensions/common/extension.h
index c4934d8cd23be31bd58ab79e6622d13ac10706ba..8d4e38ab14785dc05c40be4087b894f34ec10529 100644
--- a/extensions/common/extension.h
+++ b/extensions/common/extension.h
@@ -576,12 +576,11 @@ struct UpdatedExtensionPermissionsInfo {
   // 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