fix import crash related to ooo94186

Change-Id: I2eb8c895eef53b5b14e81c5491d7ced6ead3c40a
Reviewed-on: https://gerrit.libreoffice.org/7984
Reviewed-by: Kohei Yoshida <libreoffice@kohei.us>
Tested-by: Kohei Yoshida <libreoffice@kohei.us>