Use window.URL instead of window.webkitURL.

chrome/browser/resources/feedback/js/take_screenshot.js

 // Copyright 2013 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.
 
 /**
  * Function to take the screenshot of the current screen.
  * @param {function(HTMLCanvasElement)} callback Callback for returning the
  *                                      canvas with the screenshot on it.
  */
 function takeScreenshot(callback) {
@@ skipping 24 matching lines @@
         mandatory: {
           chromeMediaSource: 'screen',
           maxWidth: 4096,
           maxHeight: 2560
         }
       }
     },
     function(stream) {
       if (stream) {
         screenshotStream = stream;
-        video.src = window.webkitURL.createObjectURL(screenshotStream);
+        video.src = window.URL.createObjectURL(screenshotStream);
         video.play();
       }
     },
     function(err) {
       console.error('takeScreenshot failed: ' +
           err.name + '; ' + err.message + '; ' + err.constraintName);
     }
   );
 }