[xml/sgml-pkgs] Bug#841862: xml-core: configure xml-core fails when group staff does not exist

[pada]

Package: xml-core
Version: 0.16
Severity: normal

Dear Maintainer,

   * What led up to the situation?

[UPGRADE] xml-core:amd64 0.15 -> 0.16

   * What exactly did you do (or not do) that was effective (or ineffective)?

aptitude -y reinstall xml-core

   * What was the outcome of this action?

Setting up xml-core (0.16) ...
chown: invalid group: 'root:staff'
dpkg: error processing package xml-core (--configure):
 subprocess installed post-installation script returned error exit status 1

   * What outcome did you expect instead?

Execution of /var/lib/dpkg/info/xml-core.postinst without error.

   * Additional information

The files are owned by root:

# ls -ld /usr/local/share /usr/local/share/xml /usr/local/share/xml/*
drwxrwsr-x 12 root root 4096 Oct 23 23:37 /usr/local/share
drwxr-sr-x  3 root root 4096 Oct 23 23:38 /usr/local/share/xml
drwxr-sr-x  2 root root 4096 Oct 23 23:38 /usr/local/share/xml/declaration

-- System Information:
Debian Release: stretch/sid
  APT prefers testing
  APT policy: (500, 'testing'), (50, 'unstable'), (30, 'experimental')
Architecture: amd64 (x86_64)
Foreign Architectures: i386

Locale: LANG=de_DE.UTF-8, LC_CTYPE=de_DE.UTF-8 (charmap=UTF-8)
Shell: /bin/sh linked to /bin/bash
Init: systemd (via /run/systemd/system)

Versions of packages xml-core depends on:
ii  sed        4.2.2-8
ii  sgml-base  1.28

xml-core recommends no packages.

Versions of packages xml-core suggests:
ii  debhelper  10.2.2

-- no debconf information