According to ECMA-376-1:2016 17.4.63, 17.18.87, etc, all table widths are
considered preferred, and actual table layout should be determined using an
algorithm described in 17.18.87. When w:tblLayout element is omitted, or
there is no explicit width information given, it is assumed that AutoFit Table
Layout should be used, i.e. using cells content to determine final widths of
table grid. In the description of the AutoFit Table Layout algorithm, it is
stated that the table width grows to hold data, but no more than page width.

As a first approach, this commit just sets table width to 100% when there's
no width data available. TODO is to implement the AutoFit Table Layout
algorithm properly.

Change-Id: I000c548eb152c70d2c6e053f4d2b1d16e8976c27
Reviewed-on: https://gerrit.libreoffice.org/40500Tested-by: Jenkins <ci@libreoffice.org>
Reviewed-by: Mike Kaganski <mike.kaganski@collabora.com>