Fix which/METADATA am: 21cbd3f507 am: dd49be57fa am: 91f26d13c7 am: 7145a81139

Original change: https://android-review.googlesource.com/c/platform/external/rust/crates/which/+/1413813

Change-Id: I99128888ff7705d7e3be3e97c6ac34d3e98761b3