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

[automerger skipped] Only allow trusted overlays to specify FLAG_SLIPPERY am: 07e7aaff am: c7052c9c -s ours am: bb535c95 -s ours am: 734bde2b -s ours am: e8e382c0 -s ours

am skip reason: Merged-In Ia30f1c38d5ddb351c90b748ea76448a76a9dde7b with SHA-1 07e7aaff is already in history

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/16241253

Change-Id: I8319c563fa19f297132230db06bef0c39829c7ed