page load perfomance improvements...
remove the lists.js file from the <head>, which slows down page
load a lot (over 300K), and instead load it dynamically on page load.
also remove navtree_data.js from the <head>, which also slows the load
and is only used in the reference when in tree view. This file is now
loaded during the initialization of the nav tree.
diff --git a/tools/droiddoc/templates/assets/navtree.js b/tools/droiddoc/templates/assets/navtree.js
index f48e1dc..8e7a91c 100644
--- a/tools/droiddoc/templates/assets/navtree.js
+++ b/tools/droiddoc/templates/assets/navtree.js
@@ -144,8 +144,20 @@
   return null;
 }
 
+function load_navtree_data(toroot) {
+  var navtreeData = document.createElement("script");
+  navtreeData.setAttribute("type","text/javascript");
+  navtreeData.setAttribute("src", toroot+"navtree_data.js");
+  $("head").append($(navtreeData));
+} 
+
+function init_default_navtree(toroot) {
+  load_navtree_data(toroot);
+  init_navtree("nav-tree", toroot, NAVTREE_DATA);
+}
+
 function init_navtree(navtree_id, toroot, root_nodes)
-{
+{  
   var me = new Object();
   me.toroot = toroot;
   me.node = new Object();