[automerger skipped] Only allow trusted overlays to specify FLAG_SLIPPERY am:...

[automerger skipped] Only allow trusted overlays to specify FLAG_SLIPPERY am: 07e7aaff am: 6bdebc2a -s ours

am skip reason: Merged-In Ia30f1c38d5ddb351c90b748ea76448a76a9dde7b with SHA-1 0657e199 is already in history

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/16190719

Change-Id: I0888fd2e22727637aeb71c6b910d1f07403f1a03