QtCreator segfault fix in Ubuntu

QtCreator crashes on project application start, when it uses QGtkStyle and system has non-standard icon set.

$ sudo update-mime /usr/share/mime/
$ sudo update-mime-database /usr/share/mime/
$ sudo gtk-update-icon-cache ICON_THEME_PATH

Where ICON_THEME_PATH can be:
/usr/share/icons/Faenza-Darkest/ (system-wide theme install)
or
/home/<user>/.icons/Faenza-Darkest (local install)

Links
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[1] http://www.qtcentre.org/threads/35092-QT-4.7-GdkPixbuf-WARNING-**-Bug!-loader-png-didn-t-set-an-error-on-failure