New test for ClassDescriptor.
New test for ClassDescriptor.



Former-commit-id: 5eb5a3a7f05121ce76fdcc00035af97448ea50ce
julie-sullivan/phytomine,julie-sullivan/phytomine,julie-sullivan/phytomine,julie-sullivan/phytomine,julie-sullivan/phytomine,julie-sullivan/phytomine,julie-sullivan/phytomine