Also used the new OUString::number(...) methods.

Change-Id: I3174c43d56d1ae359901bb8a13fe0096f2c74808
Reviewed-on: https://gerrit.libreoffice.org/1766Reviewed-by: Luboš Luňák <l.lunak@suse.cz>
Tested-by: Luboš Luňák <l.lunak@suse.cz>