[MD Bookmarks] Add lines between items and no search results message.

chrome/browser/resources/md_bookmarks/list.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-list',
 
   properties: {
     /** @type {BookmarkTreeNode} */
     menuItem_: Object,
 
     /** @type {Array<BookmarkTreeNode>} */
     displayedList: Array,
+
+    searchTerm: String,
   },
 
   listeners: {
     'open-item-menu': 'onOpenItemMenu_',
   },
 
   /**
    * @param {Event} e
    * @private
    */
@@ skipping 50 matching lines @@
   },
 
   /** @private */
   closeDropdownMenu_: function() {
     var menu = /** @type {!CrActionMenuElement} */ (
         this.$.dropdown);
     menu.close();
   },
 
   /** @private */
-  isListEmpty_: function() {
+  emptyListMessage_: function() {
+    var emptyListMessage = this.searchTerm ? 'noSearchResults' : 'emptyList';
+    return loadTimeData.getString(emptyListMessage);
+  },
+
+  /** @private */
+  isEmptyList_: function() {
     return this.displayedList.length == 0;
-  }
+  },
 });