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

ui/file_manager/video_player/js/cast/cast_extension_discoverer.js

Index: ui/file_manager/video_player/js/cast/cast_extension_discoverer.js
diff --git a/ui/file_manager/video_player/js/cast/cast_extension_discoverer.js b/ui/file_manager/video_player/js/cast/cast_extension_discoverer.js
index ca435adf9ff99b2fc8628f9946599da0fb15ed2d..b2ff50da884c4930d2d322f60f99838577e5b954 100644
--- a/ui/file_manager/video_player/js/cast/cast_extension_discoverer.js
+++ b/ui/file_manager/video_player/js/cast/cast_extension_discoverer.js
@@ -71,13 +71,12 @@ CastExtensionDiscoverer.isExtensionInstalled_ =
   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();
 };