DevTools: reformat front-end code to match chromium style.

third_party/WebKit/Source/devtools/front_end/ui/DropDownMenu.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.Object}
- * @param {!Element} element
+ * @unrestricted
  */
-WebInspector.DropDownMenu = function(element)
-{
+WebInspector.DropDownMenu = class extends WebInspector.Object {
+  /**
+   * @param {!Element} element
+   */
+  constructor(element) {
+    super();
     /** @type {!Array.<!WebInspector.DropDownMenu.Item>} */
     this._items = [];
 
-    element.addEventListener("mousedown", this._onMouseDown.bind(this));
+    element.addEventListener('mousedown', this._onMouseDown.bind(this));
+  }
+
+  /**
+   * @param {!Event} event
+   */
+  _onMouseDown(event) {
+    if (event.which !== 1)
+      return;
+    var menu = new WebInspector.ContextMenu(event);
+    for (var item of this._items)
+      menu.appendCheckboxItem(item.title, this._itemHandler.bind(this, item.id), item.id === this._selectedItemId);
+    menu.show();
+  }
+
+  /**
+   * @param {string} id
+   */
+  _itemHandler(id) {
+    this.dispatchEventToListeners(WebInspector.DropDownMenu.Events.ItemSelected, id);
+  }
+
+  /**
+   * @param {string} id
+   * @param {string} title
+   */
+  addItem(id, title) {
+    this._items.push({id: id, title: title});
+  }
+
+  /**
+   * @param {string} id
+   */
+  selectItem(id) {
+    this._selectedItemId = id;
+  }
+
+  clear() {
+    this._items = [];
+    delete this._selectedItemId;
+  }
 };
 
 /** @typedef {{id: string, title: string}} */
 WebInspector.DropDownMenu.Item;
 
 /** @enum {symbol} */
 WebInspector.DropDownMenu.Events = {
-    ItemSelected: Symbol("ItemSelected")
+  ItemSelected: Symbol('ItemSelected')
 };
-
-WebInspector.DropDownMenu.prototype = {
-    /**
-     * @param {!Event} event
-     */
-    _onMouseDown: function(event)
-    {
-        if (event.which !== 1)
-            return;
-        var menu = new WebInspector.ContextMenu(event);
-        for (var item of this._items)
-            menu.appendCheckboxItem(item.title, this._itemHandler.bind(this, item.id), item.id === this._selectedItemId);
-        menu.show();
-    },
-
-    /**
-     * @param {string} id
-     */
-    _itemHandler: function(id)
-    {
-        this.dispatchEventToListeners(WebInspector.DropDownMenu.Events.ItemSelected, id);
-    },
-
-    /**
-     * @param {string} id
-     * @param {string} title
-     */
-    addItem: function(id, title)
-    {
-        this._items.push({id: id, title: title});
-    },
-
-    /**
-     * @param {string} id
-     */
-    selectItem: function(id)
-    {
-        this._selectedItemId = id;
-    },
-
-    clear: function()
-    {
-        this._items = [];
-        delete this._selectedItemId;
-    },
-
-    __proto__: WebInspector.Object.prototype
-};