Get rid of some <label for> misuse in browser_options.html

ui/webui/resources/css/widgets.css

 /* Copyright (c) 2012 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. */
 
 /* This file defines styles for form controls. The order of rule blocks is
  * important as there are some rules with equal specificity that rely on order
  * as a tiebreaker. These are marked with OVERRIDE. */
 
 /* Default state **************************************************************/
 
@@ skipping 238 matching lines @@
 .link-button {
   -webkit-box-shadow: none;
   background: transparent none;
   border: none;
   color: rgb(17, 85, 204);
   cursor: pointer;
   /* Input elements have -webkit-small-control which can override the body font.
    * Resolve this by using 'inherit'. */
   font: inherit;
   margin: 0;
-  padding: 0 4px;
+  padding: 0;
 }
 
 .link-button:hover {
   text-decoration: underline;
 }
 
 .link-button:active {
   color: rgb(5, 37, 119);
   text-decoration: underline;
 }
@@ skipping 18 matching lines @@
  */
 
 :-webkit-any(.checkbox, .radio) label {
   /* Don't expand horizontally: <http://crbug.com/112091>. */
   display: -webkit-inline-box;
   padding-bottom: 7px;
   padding-top: 7px;
 }
 
 :-webkit-any(.checkbox, .radio) label input ~ span {
+  -webkit-margin-end: 0.3em;
   -webkit-margin-start: 0.6em;
+  -webkit-user-select: none;
   /* Make sure long spans wrap at the same horizontal position they start. */
   display: block;
 }
 
 :-webkit-any(.checkbox, .radio) label:hover {
   color: black;
 }
 
 label > input:disabled:-webkit-any([type='checkbox'], [type='radio']) ~ span {
   color: #999;
 }