Screen reader is not auto-enabled on first login if enabled when installing

[Andrea Azzarone]

As per iso testcase the screen-reader is supposed to be auto activated if the user enabled it when installing. This is not the case in the ISO (5oct2018)

ProblemType: Bug
DistroRelease: Ubuntu 18.10
Package: ubiquity (not installed)
ProcVersionSignature: Ubuntu 4.18.0-8.9-generic 4.18.7
Uname: Linux 4.18.0-8-generic x86_64
ApportVersion: 2.20.10-0ubuntu11
Architecture: amd64
CurrentDesktop: ubuntu:GNOME
Date: Fri Oct 5 12:58:47 2018
InstallCmdLine: file=/cdrom/preseed/ubuntu.seed boot=casper initrd=/casper/initrd quiet splash --- maybe-ubiquity
InstallationDate: Installed on 2018-10-05 (0 days ago)
InstallationMedia: Ubuntu 18.10 "Cosmic Cuttlefish" - Beta amd64 (20181005)
SourcePackage: ubiquity
UpgradeStatus: No upgrade log present (probably fresh install)

[Ubuntu QA Website (ubuntuqa)]

This bug has been reported on the Ubuntu ISO testing tracker.

A list of all reports related to this bug can be found here:
http://iso.qa.ubuntu.com/qatracker/reports/bugs/1796275

[Sebastien Bacher (seb128)]

The a11y handling has been buggy since we switched away from Unity and dropped a11y-profile-manager, casper/ubiquity still call to that tool which is not on the iso anymore.

That's not a regression from bionic and too much change to refactor that this cycle but we added a trello card to our backlog for next cycle
https://trello.com/c/t1HyPc3R/89-fix-a11y-not-working-from-isolinux-nor-set-in-finale-installation-for-some-cycles

We don't want to add back the a11y-profile-manager tool because it's unmaintained, probably makes sense to revert the change that added it and go back to the old way of writting gsettings key (though that needs tweaking for lightdm->gdm)
http://launchpadlibrarian.net/240156813/casper_1.366_1.367.diff.gz