Merge "Clean up rust_test_host TEST_MAPPING after default update" am: 23d64a9487 am: 845a8d7c6c am: b89160a5d3 am: b425b8394f

Original change: https://android-review.googlesource.com/c/platform/external/rust/crates/proc-macro-hack/+/1589933

MUST ONLY BE SUBMITTED BY AUTOMERGER

Change-Id: I1f63b6bdbbb039e15c1af051405e9b62939183ce