QtIFW

Avoid NULL pointer access in case we have no data file.

Change-Id: I1954422b4f5b4af25cc8d7ccd2f0dc7bcfba1f15
Reviewed-on: http://codereview.qt.nokia.com/3320
Reviewed-by: Qt Sanity Bot <qt_sanity_bot@ovi.com>
Reviewed-by: Tim Jenssen <tim.jenssen@nokia.com>
Reviewed-by: Niels Weber <niels.2.weber@nokia.com>
Reviewed-by: Karsten Heimrich <karsten.heimrich@nokia.com>