Merge "DO NOT MERGE: ActivityManager#killBackgroundProcesses can kill caller's own app only" into tm-dev am: 1356b92c23

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/20321691

Change-Id: I8948178632b0f1b93de046f010fba787d20f751c
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>