And use std::unique_ptr not rtl::Reference.  This is not a UNO object
anyway...

Change-Id: If43da4f7e0f478b9ad8d62e5f43f04f035c31717
Reviewed-on: https://gerrit.libreoffice.org/32828Tested-by: Jenkins <ci@libreoffice.org>
Reviewed-by: Kohei Yoshida <libreoffice@kohei.us>