to the new window frame being constructed that (may) contain
the progress bar, that way such modal dialogs affect the loading
document window and not whatever window happens to be active

Change-Id: I1c7d3185e47fa316eef003b80d18b31d341b79d6
Reviewed-on: https://gerrit.libreoffice.org/44269Tested-by: Jenkins <ci@libreoffice.org>
Reviewed-by: Caolán McNamara <caolanm@redhat.com>
Tested-by: Caolán McNamara <caolanm@redhat.com>