Fix starting the app when installation finished

 Do not pass as arguments empty string, it can break
 applications which expect for example filename as first argument.

Change-Id: I5c7dd1e2fc9b441634507ad651108d2d03416224
Reviewed-by: Niels Weber <niels.weber@digia.com>
Reviewed-by: Karsten Heimrich <karsten.heimrich@digia.com>