Merge "Lock screen long-press to open wallpaper picker." into tm-qpr-dev am: b74f4255f7 am: 37635af14f

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/21062331

Change-Id: I2799c22e95bfd246481e0ec275b8ebe7947590c3
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>