Merge "Make libfutures available to DnsResolver" am: 197de3f937 am: 8761d9075f

Original change: https://android-review.googlesource.com/c/platform/external/rust/crates/futures/+/1742081

Change-Id: Ib357b96ba7989e03f8e8d2c96d2fb45df1b6bbac