Merge "Add null check for IWallpaperEngine to avoid NPE" into sc-dev am: e097d033cc

Original change: https://googleplex-android-review.googlesource.com/c/platform/packages/apps/WallpaperPicker2/+/15079491

Change-Id: I740c225ba9c50f34c17ae96c8be89d09fe1d9dc3