[MD History] Copy stats from the old history page.

chrome/browser/resources/md_history/history_list.js

 // Copyright 2015 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: 'history-list',
 
   behaviors: [HistoryListBehavior],
 
   properties: {
@@ skipping 65 matching lines @@
     /** @type {IronScrollThresholdElement} */(this.$['scroll-threshold'])
         .clearTriggers();
 
     if (!incremental) {
       this.resultLoadingDisabled_ = false;
       if (this.historyData_)
         this.splice('historyData_', 0, this.historyData_.length);
       this.fire('unselect-all');
     }
 
+    var offset = (this.historyData_ ? this.historyData_.length : 0);
+    results.forEach(function(item, index) {
+      item.index = index + offset;
+    });
+
     if (this.historyData_) {
       // If we have previously received data, push the new items onto the
       // existing array.
       results.unshift('historyData_');
       this.push.apply(this, results);
     } else {
       // The first time we receive data, use set() to ensure the iron-list is
       // initialized correctly.
       this.set('historyData_', results);
     }
   },
 
+  refreshItemIndexes: function() {
+    this.historyData_.forEach(function(item, index) {
+      item.index = index;
+    });
+  },
+
   /**
    * Called when the page is scrolled to near the bottom of the list.
    * @private
    */
   loadMoreData_: function() {
     if (this.resultLoadingDisabled_ || this.querying)
       return;
 
     this.fire('load-more-history');
   },
@@ skipping 62 matching lines @@
 
   /**
    * @param {number} index
    * @return {string}
    * @private
    */
   pathForItem_: function(index) {
     return 'historyData_.' + index;
   },
 });