Fix Closure Compilation for chrome://downloads and chrome://history

chrome/browser/resources/downloads/downloads.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.
 
 // TODO(jhawkins): Use hidden instead of showInline* and display:none.
 // TODO(hcarmona): This file is big: it may be good to split it up.
 
 /**
  * The type of the download object. The definition is based on
  * chrome/browser/ui/webui/downloads_dom_handler.cc:CreateDownloadItemValue()
@@ skipping 138 matching lines @@
    */
   addElementIfFocusable_: function(element, type) {
     if (this.shouldFocus_(element)) {
       this.addFocusableElement(element);
       element.setAttribute('column-type', type);
     }
   },
 
   /**
    * Determines if element should be focusable.
-   * @param {!Element} element
+   * @param {Element} element
    * @return {boolean}
    * @private
    */
   shouldFocus_: function(element) {
     if (!element)
       return false;
 
     // Hidden elements are not focusable.
     var style = window.getComputedStyle(element);
     if (style.visibility == 'hidden' || style.display == 'none')
@@ skipping 930 matching lines @@
     if (Date.now() - start > 50) {
       clearTimeout(resultsTimeout);
       resultsTimeout = setTimeout(tryDownloadUpdatedPeriodically, 5);
       break;
     }
   }
 }
 
 // Add handlers to HTML elements.
 window.addEventListener('DOMContentLoaded', load);