Migrate 25 crates to monorepo. am: 20f0259db0

Original change: https://android-review.googlesource.com/c/platform/external/rust/crates/futures-core/+/3242974

Change-Id: I7f9a808830010e11c766641be4f0444d171ad243
Signed-off-by: Automerger Merge Worker <[email protected]>