Refactor shared preferences

Group non-backup-able preferences separately so
we can easily backup only the backup-able ones.

Bug: 124394484
Change-Id: Ib0687c88eb74fbbd0133ed822f9e6c02aff1a5fc
diff --git a/AndroidManifest.xml b/AndroidManifest.xml
index 0192398..1415226 100755
--- a/AndroidManifest.xml
+++ b/AndroidManifest.xml
@@ -20,7 +20,7 @@
       android:name="com.android.wallpaper.NOTIFY_ROTATING_WALLPAPER_CHANGED" />
 
   <application
-      tools:replace="android:name"
+      tools:replace="android:icon,android:name"
       android:allowBackup="true"
       android:icon="@mipmap/product_logo_wallpapers_launcher_color_48"
       android:label="@string/app_name"