[automerger skipped] DO NOT MERGE Disallow Wallpaper service to launch activity from background. am: 8efec2c095 am: e6bce8f1cd -s ours am: b01acc103d -s ours

am skip reason: subject contains skip directive

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/23912846

Change-Id: Idddcf184ed9b13dd22293430ec133da5a0fe8be5
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>