Cleanup: fix some CSS comment styles (especially copyrights)

chrome/browser/resources/chromeos/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 17 matching lines @@
 a {
   color: rgb(17, 85, 204);
   text-decoration: none;
 }
 
 .icon {
   -webkit-user-select: none;
 }
 
 .icon-generic {
-  /**
-   * Can't access chrome://theme/IDR_ERROR_NETWORK_GENERIC from an untrusted
-   * renderer process, so embed the resource manually.
-   */
+  /* Can't access chrome://theme/IDR_ERROR_NETWORK_GENERIC from an untrusted
+   * renderer process, so embed the resource manually. */
   content: -webkit-image-set(
       url(../../../../components/resources/default_100_percent/neterror/error_network_generic.png) 1x,
       url(../../../../components/resources/default_200_percent/neterror/error_network_generic.png) 2x);
 }
 
 .icon-offline {
   content: -webkit-image-set(
       url(../../../../components/neterror/resources/default_100_percent/offline/100-error-offline.png) 1x,
       url(../../../../components/neterror/resources/default_200_percent/offline/200-error-offline.png) 2x);
 }
@@ skipping 152 matching lines @@
   left: 0;
   position: absolute;
   top: 0;
   width: 100vw;
   z-index: 1;
 }
 
 #offline-resources {
   display: none;
 }