[MD History] Factor out a common HistoryListBehavior.

chrome/browser/resources/md_history/grouped_list.js

Index: chrome/browser/resources/md_history/grouped_list.js
diff --git a/chrome/browser/resources/md_history/grouped_list.js b/chrome/browser/resources/md_history/grouped_list.js
index 9d14bfc9e458fd1572a93cb7e6ee5cd46b7e15a2..b7520466a6f4d0ce81cab5d00e59323773ea7fab 100644
--- a/chrome/browser/resources/md_history/grouped_list.js
+++ b/chrome/browser/resources/md_history/grouped_list.js
@@ -21,6 +21,8 @@ var HistoryGroup;
 Polymer({
   is: 'history-grouped-list',
 
+  behaviors: [HistoryListBehavior],
+
   properties: {
     // An array of history entries in reverse chronological order.
     historyData: {
@@ -156,21 +158,36 @@ Polymer({
         visits, itemIndex, this.searchedTerm);
   },
 
-  hasResults_: function(historyDataLength) {
-    return historyDataLength > 0;
+  /**
+   * @param {number} groupIndex
+   * @param {number} domainIndex
+   * @param {number} itemIndex
+   * @return {string}
+   * @private
+   */
+  pathForItem_: function(groupIndex, domainIndex, itemIndex) {
+    return [
+      'groupedHistoryData_', groupIndex, 'domains', domainIndex, 'visits',
+      itemIndex
+    ].join('.');
   },
 
+  /**
+   * @param {HistoryDomain} domain
+   * @return {string}
+   * @private
+   */
   getWebsiteIconStyle_: function(domain) {
     return 'background-image: ' +
         cr.icon.getFaviconImageSet(domain.visits[0].url);
   },
 
+  /**
+   * @param {boolean} expanded
+   * @return {string}
+   * @private
+   */
   getDropdownIcon_: function(expanded) {
     return expanded ? 'cr:expand-less' : 'cr:expand-more';
   },
-
-  noResultsMessage_: function(searchedTerm) {
-    var messageId = searchedTerm !== '' ? 'noSearchResults' : 'noResults';
-    return loadTimeData.getString(messageId);
-  },
 });