Merge "Fixes improbable NPE in WallpaperManagerService dump()" into udc-dev am: 9e5276fa am: d58987fd

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/22162905



Change-Id: I307824bb8ba96278bb5c0bdb60de0fa40db35bb3
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>