If the ``use_percona_upstream`` value is changed from True to False,
don't remove the existing repository. This is also the source of a bug
in Mitaka: We were installing the repo by default and installed the
percona-xtrabackup tool with a deb file. If another playbook/role
installed percona-xtrabackup, it would override (and probably upgrade)
the deb installed version, which is undesired.
Change-Id: I2ccc2904d0d4244dc0792411b49763cc3f7e2e22
Closes-Bug: 1653947
Signed-off-by: Jean-Philippe Evrard <jean-philippe.evrard@rackspace.co.uk>
2aa7f1ca8a