Doc change: updates for preview content.

Change-Id: Ife06f0e5b3ef6950d5d6fe452940c8dd87ed89ea
diff --git a/docs/html/jd_collections.js b/docs/html/jd_collections.js
index 421f87a..050bf10 100644
--- a/docs/html/jd_collections.js
+++ b/docs/html/jd_collections.js
@@ -1383,11 +1383,15 @@
     "title": "",
     "resources": [
       "preview/overview.html",
-      "preview/api-overview.html",
+      "preview/download.html",
       "preview/setup-sdk.html",
       "preview/samples.html",
-      "preview/reference.html",
-      "preview/support.html"
+      "preview/support.html",
+      "preview/api-overview.html",
+      "preview/features/runtime-permissions.html",
+      "preview/api-changes.html",
+      "preview/api-overview.html",
+      "preview/backup/index.html",
     ]
   },
   "autolanding": {