Merge "Clean up rust_test_host TEST_MAPPING after default update" am: 8e7b3701dc am: 741136111a am: 5088056049

Original change: https://android-review.googlesource.com/c/platform/external/rust/crates/cexpr/+/1590594

MUST ONLY BE SUBMITTED BY AUTOMERGER

Change-Id: I0c67ae729b4da27bdcf37c3a146a6c9f0be58c59