docs: Fixing typo on Auto Backup for Apps page.

See first comment for doc stage location.

bug: 21410471
Change-Id: I4e92a7d0e2056c02755d1d9ba403dbafcbe59490
diff --git a/docs/html/preview/backup/index.jd b/docs/html/preview/backup/index.jd
index 5953e30..bf91662 100644
--- a/docs/html/preview/backup/index.jd
+++ b/docs/html/preview/backup/index.jd
@@ -27,8 +27,8 @@
 
 <p>
   Automatic backups are enabled for all apps installed on devices running the Android M Preview. No
-  additional app code is required. The system provides users with the ability opt out of automatic
-  data backups. You can also choose to limit what data from your app is backed up.
+  additional app code is required. The system provides users with the ability to opt out of
+  automatic data backups. You can also choose to limit what data from your app is backed up.
 </p>
 
 <p>