Remember all wallpapers' backup-allow state

...not just system wallpapers.

Bug 30751829

Change-Id: If9f5df33e587e31080a7e65b1cbcae03f9a39f3c
diff --git a/services/core/java/com/android/server/wallpaper/WallpaperManagerService.java b/services/core/java/com/android/server/wallpaper/WallpaperManagerService.java
index 7166028..64f79e1 100644
--- a/services/core/java/com/android/server/wallpaper/WallpaperManagerService.java
+++ b/services/core/java/com/android/server/wallpaper/WallpaperManagerService.java
@@ -1400,9 +1400,7 @@
                     wallpaper.whichPending = which;
                     wallpaper.setComplete = completion;
                     wallpaper.cropHint.set(cropHint);
-                    if ((which & FLAG_SYSTEM) != 0) {
-                        wallpaper.allowBackup = allowBackup;
-                    }
+                    wallpaper.allowBackup = allowBackup;
                 }
                 return pfd;
             } finally {