QVariant operator ==() for QIcons returns false all the time

When setting an Icon to a QStandardItem, it always fires the dataChanged() signal. Even if the icon is the same.
It can lead to infinite loops.
There seem to be a good fix by doing in qguivariant::compare():
case QVariant::Icon:
return *v_cast<QIcon>(a).cacheKey() == *v_cast<QIcon>(b).cacheKey();