bug#28704: 27.0.50; Sorting packages list slow when using display-line-numbers-type visual

[martin rudalics]

> Then run: M-x list-packages
>
> Then click on one of the column headers to trigger sorting by that
> column, e.g. Status. Emacs will freeze for a couple of minutes.
>
> Profiler reveals:
>
> - command-execute                                               25144  98%
>   - call-interactively                                           25144  98%
>    - funcall-interactively                                       25144  98%
>     - tabulated-list-col-sort                                    24960  97%
>      - tabulated-list--sort-by-column-name                       24960  97%
>       - tabulated-list-print                                     24956  97%
>        - apply                                                   24916  97%
>         - tabulated-list-print-entry                             24903  97%
>          - tabulated-list-line-number-width                      24736  96%
>             #<compiled 0x2a38871>                                    2   0%
>
> So it looks like all of the time is spent inside 
tabulated-list-line-number-width.

‘tabulated-list-print’ should calculate ‘line-number-display-width’ once
and ‘tabulated-list-line-number-width’ should use that value.

martin