[Devtools] Cleanup DataGrid's typecast and identifier naming

third_party/WebKit/Source/devtools/front_end/network/EventSourceMessagesView.js

 // Copyright 2014 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
  * @extends {WebInspector.VBox}
  * @param {!WebInspector.NetworkRequest} request
  */
 WebInspector.EventSourceMessagesView = function(request)
 {
     WebInspector.VBox.call(this);
     this.registerRequiredCSS("network/eventSourceMessagesView.css");
     this.element.classList.add("event-source-messages-view");
     this._request = request;
 
-    var columns = [
+    var columns = /** @type {!Array<!WebInspector.DataGrid.ColumnDescriptor>} */ ([
         {id: "id", title: WebInspector.UIString("Id"), sortable: true, weight: 8},
         {id: "type", title: WebInspector.UIString("Type"), sortable: true, weight: 8},
         {id: "data", title: WebInspector.UIString("Data"), sortable: false, weight: 88},
         {id: "time", title: WebInspector.UIString("Time"), sortable: true, weight: 8}
-    ];
+    ]);
 
     this._dataGrid = new WebInspector.SortableDataGrid(columns);
     this._dataGrid.setStickToBottom(true);
     this._dataGrid.markColumnAsSortedBy("time", WebInspector.DataGrid.Order.Ascending);
     this._sortItems();
     this._dataGrid.addEventListener(WebInspector.DataGrid.Events.SortingChanged, this._sortItems, this);
 
     this._dataGrid.setName("EventSourceMessagesView");
     this._dataGrid.asWidget().show(this.element);
 };
@@ skipping 18 matching lines @@
      * @param {!WebInspector.Event} event
      */
     _messageAdded: function(event)
     {
         var message = /** @type {!WebInspector.NetworkRequest.EventSourceMessage} */ (event.data);
         this._dataGrid.insertChild(new WebInspector.EventSourceMessageNode(message));
     },
 
     _sortItems: function()
     {
-        var sortColumnIdentifier = this._dataGrid.sortColumnIdentifier();
-        if (!sortColumnIdentifier)
+        var sortColumnId = this._dataGrid.sortColumnId();
+        if (!sortColumnId)
             return;
-        var comparator = WebInspector.EventSourceMessageNode.Comparators[sortColumnIdentifier];
+        var comparator = WebInspector.EventSourceMessageNode.Comparators[sortColumnId];
         if (!comparator)
             return;
         this._dataGrid.sortNodes(comparator, !this._dataGrid.isSortOrderAscending());
     },
 
     __proto__: WebInspector.VBox.prototype
 };
 
 /**
  * @constructor
@@ skipping 27 matching lines @@
     var bValue = b._message[field];
     return aValue < bValue ? -1 : aValue > bValue ? 1 : 0;
 };
 
 /** @type {!Object.<string, !WebInspector.SortableDataGrid.NodeComparator>} */
 WebInspector.EventSourceMessageNode.Comparators = {
     "id": WebInspector.EventSourceMessageNodeComparator.bind(null, "eventId"),
     "type": WebInspector.EventSourceMessageNodeComparator.bind(null, "eventName"),
     "time": WebInspector.EventSourceMessageNodeComparator.bind(null, "time")
 };