Request Document: go/android-rust-importing-crates
For CL Reviewers: go/android3p#cl-review
For Build Team: go/ab-third-party-imports
Bug: 360116764
Bug: 359646531
Test: none

Change-Id: I567d104d028eeb63a1b9f3bfd57c60d93ed48ffb
Signed-off-by: Neill Kapron <nkapron@google.com>