Creating a role with the same name as the user name with object ownership enabled can cause INVALIDATE METADATA to hang

[localhost:21000] default> create database foo;
[localhost:21000] default> create role impdev;
[localhost:21000] default> grant all on server to role impdev;
[localhost:21000] default> grant role impdev to group impdev;
[localhost:21000] default> invalidate metadata; -- this will hang