Merge "Keep showing wallpaper when starting an app immediatly after unlock." into sc-v2-dev am: efcf2e8553 am: ef310224aa

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/16978905

Change-Id: Ica06f3ae8505d83442e7c1cb1c028683cf679196