QtIFW

Expand the root item before resizing the columns.

Makes sure that at least the first node is fully visible.

Change-Id: I5c9f476b2947276d81ac4571a824db5cf4e7b7ae
Reviewed-on: http://codereview.qt.nokia.com/4251
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>