Merge "Provide a flag library for rust code" into main am: 9670ad20

Original change: https://android-review.googlesource.com/c/platform/packages/modules/Bluetooth/+/3248691



Change-Id: I8f2c2797d0c8b14c936efc7f1f9850d0c81ea327
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>