Comment 2 for bug 205444

The following quick patch attempts to solve two problems in the Gutsy /etc/bash_completion:

  * Don't "set -v" or "set +v" if it's already set
  * If BASH_COMPLETION or BASH_COMPLETION_DIR are declared readonly, don't even attempt to modify them

The latter would (if my quick analysis isn't completely up the creek) cause scripts which sourced /etc/bash_completion to exit with an error from within /etc/bash_completion instead of completing if bash_completion had already been executed previously. This includes, but is not limited to, /etc/skel/.bashrc and thus also anything which includes .bashrc, such as /etc/skel/.profile