Merge "Turn on Wallpaper Fullscreen preview" into tm-qpr-dev am: 270bd3c80b

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/21164327

Change-Id: Ic6efc8c3b0132bf6d81fb1bdc314b15d6c266c9b
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>