[WIP] MD Bookmarks Drag and Drop.

chrome/browser/resources/md_bookmarks/folder_node.js

 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 Polymer({
   is: 'bookmarks-folder-node',
 
   behaviors: [
     bookmarks.StoreClient,
   ],
@@ skipping 100 matching lines @@
     return this.depth + 1;
   },
 
   /**
    * @param {string} itemId
    * @private
    * @return {boolean}
    */
   isFolder_: function(itemId) {
     return !this.getState().nodes[itemId].url;
-  }
+  },
+
+  /**
+   * @private
+   * @return {boolean}
+   */
+  isRootFolder_: function() {
+    return this.depth == 0;
+  },
 });