Merge "Fix security vulnerability allowing apps to start from background" into sc-dev am: 408cac13c0 am: 3b2f30dfc9 am: 6a8afefe7d am: 2b60d838b9

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/26941037

Change-Id: I8e338fb500ef6acfd41cca13fe463014538f87c2
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>