Introduce a separate wallpaper_file type for the wallpaper file.
diff --git a/file_contexts b/file_contexts
index 550fa9a..9c8325a 100644
--- a/file_contexts
+++ b/file_contexts
@@ -118,6 +118,8 @@
 /data/misc/wifi(/.*)?		u:object_r:wifi_data_file:s0
 # App sandboxes
 /data/data/.*		u:object_r:app_data_file:s0
+# Wallpaper file.
+/data/data/com.android.settings/files/wallpaper	u:object_r:wallpaper_file:s0
 #############################
 # efs files
 #