[MD History] Add grouped history toolbar.

chrome/browser/resources/md_history/history_toolbar.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.
 
 /**
  * @constructor
  * @implements {SearchFieldDelegate}
  * @param {!HistoryToolbarElement} toolbar This history-toolbar.
  */
 function ToolbarSearchFieldDelegate(toolbar) {
@@ skipping 25 matching lines @@
       reflectToAttribute: true
     },
 
     // The most recent term entered in the search field. Updated incrementally
     // as the user types.
     searchTerm: {
       type: String,
       value: ''
     },
 
-    // True if it's searching at the backend.
+    // True if waiting on the search backend.
     searching: {
       type: Boolean,
       value: false
     },
+
+    // Whether domain-grouped history is enabled.
+    isGroupedMode: {
+      type: Boolean,
+      reflectToAttribute: true,
+    },
+
+    // The period to search over. Matches BrowsingHistoryHandler::Range.
+    groupedRange: {
+      type: Number,
+      value: 0,
+      reflectToAttribute: true
+    },
+
+    // The start time of the query range.
+    queryStartTime: String,
+
+    // The end time of the query range.
+    queryEndTime: String,
   },
 
   /**
    * Changes the toolbar background color depending on whether any history items
    * are currently selected.
    * @private
    */
   changeToolbarView_: function() {
     this.itemsSelected_ = this.count > 0;
   },
@@ skipping 40 matching lines @@
   /**
    * If the user is a supervised user the delete button is not shown.
    * @private
    */
   deletingAllowed_: function() {
     return loadTimeData.getBoolean('allowDeletingHistory');
   },
 
   numberOfItemsSelected_: function(count) {
     return count > 0 ? loadTimeData.getStringF('itemsSelected', count) : '';
+  },
+
+  getHistoryInterval_: function(queryStartTime, queryEndTime) {
+    // TODO(calamity): Fix the format of these dates.
+    return loadTimeData.getStringF(
+      'historyInterval', queryStartTime, queryEndTime);
   }
 });