settings: fix search

chrome/browser/resources/options/options_page.js

Index: chrome/browser/resources/options/options_page.js
diff --git a/chrome/browser/resources/options/options_page.js b/chrome/browser/resources/options/options_page.js
index 8a1b37531310e8c9e0a3c05fa35ddb06fcaefd30..a10ab3c9e557c81b131dd7de85a248452af38e54 100644
--- a/chrome/browser/resources/options/options_page.js
+++ b/chrome/browser/resources/options/options_page.js
@@ -500,6 +500,11 @@ cr.define('options', function() {
         overlay.associatedSection =
             this.findSectionForNode_(associatedControls[0]);
       }
+
+      // Sanity check.
+      for (var i = 0; i < associatedControls.length; ++i) {
+        assert(associatedControls[i], 'Invalid element passed.');
+      }
     }
 
     // Reverse the button strip for views. See the documentation of