In certain sandboxes, we have libQtDBus, but not D-Bus. QtDBus shouldn't
crash in that case, but return non-working QDBusConnection instances
instead.
Change-Id: Ia4ac78d1197bae50cde0cf07e6fc66fc25b85011
Reviewed-on: http://codereview.qt.nokia.com/1319
Reviewed-by: Qt Sanity Bot <qt_sanity_bot@ovi.com>
Reviewed-by: Robert Griebl <robert.griebl@nokia.com>