Focus events during dispose, unfortunate incoming a11y events, etc.

Change-Id: Iee296b767839904f5f330786891bc2513ca06c0c
Reviewed-on: https://gerrit.libreoffice.org/16672Reviewed-by: Michael Meeks <michael.meeks@collabora.com>
Tested-by: Michael Meeks <michael.meeks@collabora.com>
Reviewed-on: https://gerrit.libreoffice.org/16686Reviewed-by: Caolán McNamara <caolanm@redhat.com>
Tested-by: Caolán McNamara <caolanm@redhat.com>