Remove -webkit-*-before/after in:

chrome/browser/resources/chromeos/login/oobe_screen_terms_of_service.css

 /* Copyright (c) 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.
  */
 
 #terms-of-service {
   padding: 70px 17px 21px;
 }
 
 #tos-container {
   border: 1px solid #d9d9d9;
   height: 222px;
 }
 
 #terms-of-service .step-contents {
-  -webkit-margin-after: 49px;
   -webkit-margin-start: 32px;
+  margin-bottom: 49px;
 }
 
 #terms-of-service h1 {
   font-size: 100%;
   font-weight: normal;
   margin: 0 0 8px 0;
   width: 630px;
 }
 
 #tos-subheading {
@@ skipping 56 matching lines @@
   display: none;
 }
 
 .step.error #tos-error {
   display: -webkit-flex;
 }
 
 #terms-of-service.error #tos-back-button {
   -webkit-margin-end: 1px;
 }