Merge "Allow precompiled sepolicy w/o system_ext/product" am: b56165cce3

Original change: https://android-review.googlesource.com/c/platform/system/core/+/1626229

MUST ONLY BE SUBMITTED BY AUTOMERGER

Change-Id: I9d1c7e69f10c2a17631aedc20b1dd5d826c02a30