We should only warn about missing a11y plugins if iface is 0, since
we obviously have the plugin otherwise.
This got triggered by that a visible widget got destructed, which in
turn called hide(), which ultimately ended up calling
QAccessible::updateAccessibility(QAccessible::ObjectHide).
When QAccessibleEvent::accessibleInterface() then called
queryAccessibleInterface(), QAI::isValid() would return false because
the widget was in its destructor.
Change-Id: If655e00e7bb3737a39e24e26dbd1e23edd515bf5
Reviewed-by: Friedemann Kleint <Friedemann.Kleint@digia.com>
Reviewed-by: Frederik Gladhorn <frederik.gladhorn@digia.com>
3a3e9b74eb