Fix flash of icon border when network error page is loaded

chrome/renderer/resources/neterror.css

 /* 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. */
 
 /* Don't use the main frame div when the error is in a subframe. */
 html[subframe] #main-frame-error {
   display: none;
 }
 
 /* Don't use the subframe error div when the error is in a main frame. */
@@ skipping 19 matching lines @@
   margin: 10px 0;
 }
 
 a {
   color: rgb(17, 85, 204);
   text-decoration: none;
 }
 
 .icon {
   -webkit-user-select: none;
-  content: '';
+  display: inline-block;
 }
 
 .icon-generic {
   /**
    * Can't access chrome://theme/IDR_ERROR_NETWORK_GENERIC from an untrusted
    * renderer process, so embed the resource manually.
    */
   content: -webkit-image-set(
       url(default_100_percent/common/error_network_generic.png) 1x,
       url(default_200_percent/common/error_network_generic.png) 2x);
@@ skipping 395 matching lines @@
     overflow: inherit;
     padding: 0 8px;
   }
 }
 
 @media (max-width: 120px) {
   button {
     width: auto;
   }
 }