docs: add support for an infinite number of nested lists in side nav

Change-Id: I9e0fa672e20067f3e09f56560e7d11847d0b9388
diff --git a/tools/droiddoc/templates-sdk/assets/js/docs.js b/tools/droiddoc/templates-sdk/assets/js/docs.js
index f1fbfff..376f9b8 100644
--- a/tools/droiddoc/templates-sdk/assets/js/docs.js
+++ b/tools/droiddoc/templates-sdk/assets/js/docs.js
@@ -138,12 +138,13 @@
   var $selListItem;
   if ($selNavLink.length) {
     $selListItem = $selNavLink.closest('li');
-
     $selListItem.addClass('selected');
-    $selListItem.closest('li.nav-section').addClass('expanded');
-    $selListItem.closest('li.nav-section').children('ul').show();
-    $selListItem.closest('li.nav-section').parent().closest('li.nav-section').addClass('expanded');
-    $selListItem.closest('li.nav-section').parent().closest('ul').show();
+    
+    // Traverse up the tree and expand all parent nav-sections
+    $selNavLink.parents('li.nav-section').each(function() {
+      $(this).addClass('expanded');
+      $(this).children('ul').show();
+    });
     
     
   //  $selListItem.closest('li.nav-section').closest('li.nav-section').addClass('expanded');