QAbstractState comparison methods return wrong result for sibling states

This is an excerpt from QStateMachinePrivate::stateEntryLessThan:

if (s1->parent() == s2->parent()) {
    return s1->children().indexOf(s1)
        < s2->children().indexOf(s2);
}

Because QObject can't be its own child, when the two QAbstractState instances have same parent, method always returns (-1 < -1) => false. Apparently the correct code should be:

if (s1->parent() == s2->parent()) {
    return s1->parent()->children().indexOf(s1)
        < s2->parent()->children().indexOf(s2);
}

The same fix also applies to QStateMachinePrivate::stateExitLessThan.