Merge "cargo2rulesmk.py: Support customizing rustc" into main am: a3f72f8382 am: 76ebade138 am: 13b5d1261a am: fcb180b6b5 am: f6d2f8b146

Original change: https://android-review.googlesource.com/c/platform/development/+/2726754

Change-Id: I38de459500dbe0b78c3d2abe60b960c4a6a0048f
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>