Added "select all/none" checkbox.

chrome/browser/resources/shared/js/cr/ui/array_data_model.js

 // Copyright (c) 2011 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.
 
 /**
  * @fileoverview This is a data model representin
  */
 
 cr.define('cr.ui', function() {
   const EventTarget = cr.EventTarget;
@@ skipping 59 matching lines @@
         this.compareFunctions_ = {};
       }
       this.compareFunctions_[field] = compareFunction;
     },
 
     isSortable: function(field) {
       return this.compareFunctions_ && field in this.compareFunctions_;
     },
 
     /**
+     * Returns true if the field has a compare function.
+     * @param {string} field The field to check.
+     * @return {boolean} True if the field is sortable.
+     */
+    isSortable: function(field) {
+      return this.compareFunctions_ && field in this.compareFunctions_;
+    },
+
+    /**
      * Returns current sort status.
      * @return {!Object} Current sort status.
      */
     get sortStatus() {
       if (this.sortStatus_) {
         return this.createSortStatus(
             this.sortStatus_.field, this.sortStatus_.direction);
       } else {
         return this.createSortStatus(null, null);
       }
@@ skipping 268 matching lines @@
       if (a > b)
         return 1;
       return 0;
     }
   };
 
   return {
     ArrayDataModel: ArrayDataModel
   };
 });