Previously, if an earlier column wished for the entire table width,
then none of the other columns could adjust their size, even if
they only wanted one more character. This slight change gives
every column a chance to "wish" for an equal portion, and
still gives the earlier columns a chance to maximize.

So, this should implement very similarly to before, thus workflow
should not be impacted.

Change-Id: I11e8b94ce333735aa92b5388af6319f8eb0ccc51
Reviewed-on: https://gerrit.libreoffice.org/60027
Tested-by: Jenkins
Reviewed-by: Justin Luth <justin_luth@sil.org>