MD Settings: adjust iron-list focus row behaviors.

ui/webui/resources/js/cr/ui/focus_row.js

Index: ui/webui/resources/js/cr/ui/focus_row.js
diff --git a/ui/webui/resources/js/cr/ui/focus_row.js b/ui/webui/resources/js/cr/ui/focus_row.js
index 652b0353f61a2ab23e4fb8dda774747ac55322f6..b2488510e13ef70d75d23aace37e97d39df4a50b 100644
--- a/ui/webui/resources/js/cr/ui/focus_row.js
+++ b/ui/webui/resources/js/cr/ui/focus_row.js
@@ -105,13 +105,18 @@ cr.define('cr.ui', function() {
      * to indicate they're equivalent.
      *
      * @param {string} type The type of element to track focus of.
-     * @param {string} query The selector of the element from this row's root.
+     * @param {string|HTMLElement} query The selector of the element from this

[hcarmona, 2017/03/16 21:31:54]

nit: rename |query| to |selector|

[scottchen, 2017/03/17 21:26:59]

good idea, wasn't sure what to name it.

+     *    row's root, or the element itself.
      * @return {boolean} Whether a new item was added.
      */
     addItem: function(type, query) {
       assert(type);
 
-      var element = this.root.querySelector(query);
+      var element;
+      if (query instanceof HTMLElement)
+        element = query;
+      else
+        element = this.root.querySelector(/** @type {string} */ (query));
       if (!element)
         return false;