const internal/abi.MapNeedKeyUpdate

3 uses

	internal/abi (current package)
		map.go#L47: 	MapNeedKeyUpdate = 1 << iota
		map.go#L54: 	return mt.Flags&MapNeedKeyUpdate != 0

	reflect
		map.go#L74: 		mt.Flags |= abi.MapNeedKeyUpdate