Correct indentation, JSDoc, etc... to comply with closure linter.

ui/file_manager/video_player/js/cast/cast_extension_discoverer.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.
 
 'use strict';
 
 /**
  * Discover the ID of installed cast extension.
  * @constructor
  */
@@ skipping 53 matching lines @@
  * @param {function(boolean)} callback Callback to notify the result.
  * @private
  */
 CastExtensionDiscoverer.isExtensionInstalled_ =
     function(extensionId, callback) {
 
   var xhr = new XMLHttpRequest();
   var url = 'chrome-extension://' + extensionId + '/cast_sender.js';
   xhr.open('GET', url, true);
   xhr.onerror = function() { callback(false); };
-  xhr.onreadystatechange =
-      /** @param {*} response */
-      function(event) {
-        if (xhr.readyState == 4 && xhr.status === 200) {
-          // Cast extension found.
-          callback(true);
-        }
-      }.wrap(this);
+  /** @param {*} event */
+  xhr.onreadystatechange = function(event) {
+    if (xhr.readyState == 4 && xhr.status === 200) {
+      // Cast extension found.
+      callback(true);
+    }
+  }.wrap(this);
   xhr.send();
 };