Add rust_test and update TEST_MAPPING am: 2073710dde am: 5eb6104876 am: 276a00db19

Original change: https://android-review.googlesource.com/c/platform/external/rust/crates/rustc-hash/+/1365658

Change-Id: Id815a6be22633e86f51c4d8894447383fc57f5ac