[NFC] Silenced unused private field warning.
[NFC] Silenced unused private field warning.

Removed the field.

glessard/swift,JGiola/swift,roambotics/swift,apple/swift,benlangmuir/swift,apple/swift,JGiola/swift,benlangmuir/swift,apple/swift,JGiola/swift,glessard/swift,benlangmuir/swift,roambotics/swift,benlangmuir/swift,roambotics/swift,benlangmuir/swift,JGiola/swift,benlangmuir/swift,apple/swift,roambotics/swift,JGiola/swift,glessard/swift,glessard/swift,glessard/swift,apple/swift,roambotics/swift,apple/swift,roambotics/swift,glessard/swift,JGiola/swift