tomteb/carbon-lang: == Clone of https://github.com/carbon-language/carbon-lang.git == @ 87e588c3349e703ade0ad8dc738c403473ff50a1

Strom: 87e588c334

Geoff Romer 6985ecb1d4 Replace GetCurrentReturnSlot with GetReturnedVarParam (#6571)		3 mesiacov pred
..
basics.carbon	6985ecb1d4 Replace GetCurrentReturnSlot with GetReturnedVarParam (#6571)	3 mesiacov pred
import.carbon	c5eba90317 Change `Destroy` to use a `CustomWitness` instead of a blanket impl (#6512)	4 mesiacov pred