Type check PDF plugin JS code, down to 53 errors.

chrome/browser/resources/pdf/toolbar_manager.js

 // Copyright 2015 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.
 
 'use strict';
 
 /** Idle time in ms before the UI is hidden. */
 var HIDE_TIMEOUT = 2000;
 /** Time in ms after force hide before toolbar is shown again. */
 var FORCE_HIDE_TIMEOUT = 1000;
@@ skipping 118 matching lines @@
 
         if (interval != 0)
           return movement / interval > SHOW_VELOCITY;
       }
     }
     return false;
   },
 
   /**
    * Wrapper around Date.now() to make it easily replaceable for testing.
-   * @return {int}
+   * @return {number}
    * @private
    */
   getCurrentTimestamp_: function() {
     return Date.now();
   },
 
   /**
    * Display both UI toolbars.
    */
   showToolbars: function() {
@@ skipping 93 matching lines @@
    * the UI.
    * @private
    */
   resizeDropdowns_: function() {
     if (!this.toolbar_)
       return;
     var lowerBound = this.window_.innerHeight - this.zoomToolbar_.clientHeight;
     this.toolbar_.setDropdownLowerBound(lowerBound);
   }
 };