05b5c6f2fb
If there was a lock wallpaper, and the user then sets the lock screen to the same as the system wallpaper, the "-1" value for the lock wallpaper ID (which represents 'use the same as the system wallpaper') was not remembered. This caused a backup per-day to be made for the wallpaper. Fixes: 140995339 Test: atest WallpaperBackupAgentTests Change-Id: Ia171d21e8c12755bdae418a52ca854a4bca3a695