[automerger skipped] Disallow system apps to be installed/updated as instant. am: 3fb2504a99 -s ours

am skip reason: Merged-In Idd89a6dd72f0e68259095f677185f0494391025c with SHA-1 c61ee9f452 is already in history

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/25715851

Change-Id: I92c864cd7eb5426ed05da42b22a2f15cac19e094
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>