Typecheck JS files for chrome://history

ui/webui/resources/js/cr/ui/menu.js

 // Copyright (c) 2012 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.
 
 cr.define('cr.ui', function() {
 
   /** @const */ var MenuItem = cr.ui.MenuItem;
 
   /**
    * Creates a new menu element. Menu dispatches all commands on the element it
@@ skipping 70 matching lines @@
     /**
      * Clears menu.
      */
     clear: function() {
       this.textContent = '';
     },
 
     /**
      * Walks up the ancestors of |el| until a menu item belonging to this menu
      * is found.
-     * @param {Element} el The element to start searching from.
+     * @param {Node} el The element to start searching from.

[Dan Beam, 2014/08/19 00:31:53]

s/el/node

[Vitaly Pavlenko, 2014/08/19 18:30:27]

Done.

      * @return {cr.ui.MenuItem} The found menu item or null.
      * @private
      */
     findMenuItem_: function(el) {
       while (el && el.parentNode != this) {
         el = el.parentNode;
       }
       return assertInstanceof(el, MenuItem);
     },
 
     /**
      * Handles mouseover events and selects the hovered item.
      * @param {Event} e The mouseover event.
      * @private
      */
     handleMouseOver_: function(e) {
-      var overItem = this.findMenuItem_(e.target);
+      var overItem = this.findMenuItem_(/** @type {Element} */(e.target));
       this.selectedItem = overItem;
     },
 
     /**
      * Handles mouseout events and deselects any selected item.
      * @param {Event} e The mouseout event.
      * @private
      */
     handleMouseOut_: function(e) {
       this.selectedItem = null;
@@ skipping 141 matching lines @@
       oldSelectedItem.selected = false;
       oldSelectedItem.blur();
     }
     var item = this.selectedItem;
     if (item)
       item.selected = true;
   }
 
   /**
    * The selected menu item.
-   * @type {number}
+   * type {number}

[Dan Beam, 2014/08/19 00:31:53]

make a real jsdoc param or remove

[Vitaly Pavlenko, 2014/08/19 18:30:27]

Not done. We still have no type checking for Object.defineProperty() with types
other than string and boolean. I'd like to remain type info in comments for us
to be easy to implement and enable it in the future.

    */
   cr.defineProperty(Menu, 'selectedIndex', cr.PropertyKind.JS,
       selectedIndexChanged);
 
   // Export
   return {
     Menu: Menu
   };
 });