Startcenter: double click opens file only once

Change-Id: I0d99a905cc8c94d39bfe802b2c597275c81f0b4f
(cherry picked from commit c22f8faa7103a8a49b6a872293104b50f9c5d951)
Reviewed-on: https://gerrit.libreoffice.org/7332
Reviewed-by: Jan Holesovsky <kendy@collabora.com>
Tested-by: Jan Holesovsky <kendy@collabora.com>