Prevent non-admin users from deleting system apps. am: 6c870e1579 am: 15ab50ec29 am: d719add201 am: a6038bd5cc

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/17408864

Change-Id: I688f747552cc32683f855c777762bf135291eaf7
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>