Merge "Only allow .scl files to load other .scl files" into main am: 7c860771 am: f85e863d

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



Change-Id: I5da2a5e977e8a46fada134d061fd909728a67250
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>