Merge "Only allow .scl files to load other .scl files" into main am: 7c860771

Original change: https://android-review.googlesource.com/c/platform/build/+/2820037



Change-Id: Id6e4070155b608d2845db563275057cbfdcf1d58
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>