Associate the instant label text with a specific checkbox.

chrome/browser/resources/options/browser_options.js

 // Copyright (c) 2011 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.
 
 cr.define('options', function() {
   const OptionsPage = options.OptionsPage;
   const ArrayDataModel = cr.ui.ArrayDataModel;
 
   //
   // BrowserOptions class
@@ skipping 153 matching lines @@
     },
 
     /**
      * Called to set the Instant field trial status.
      * @param {boolean} enabled If true, the experiment is enabled.
      * @private
      */
     setInstantFieldTrialStatus_: function(enabled) {
       $('instantEnabledCheckbox').hidden = enabled;
       $('instantFieldTrialCheckbox').hidden = !enabled;
+      $('instantLabel').htmlFor = enabled ? 'instantFieldTrialCheckbox'
+                                          : 'instantEnabledCheckbox';
     },
 
     /**
      * Called when the value of the homepage-use-NTP pref changes.
      * Updates the disabled state of the homepage text field.
      * Notice that the text field can be disabled for other reasons too
      * (it can be managed by policy, for instance).
      * @param {Event} event Change event.
      * @private
      */
@@ skipping 170 matching lines @@
   BrowserOptions.setInstantFieldTrialStatus = function(enabled) {
     BrowserOptions.getInstance().setInstantFieldTrialStatus_(enabled);
   };
 
   // Export
   return {
     BrowserOptions: BrowserOptions
   };
 
 });