Merge "Move logic for detecting different kinds of externs to cargo_out." into main am: 8df3496e01

Original change: https://android-review.googlesource.com/c/platform/development/+/2711993

Change-Id: I89a0f559d8834cb1b9ad874584c6f135850e912f
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>