WebUI: Fix violations of no-extra-semi lint rule.

chrome/browser/resources/chromeos/switch_access/test_support.js

 // Copyright 2017 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.
 
-function TestSupport() {};
+function TestSupport() {}
 
 TestSupport.prototype = {
   /**
    * Connect |parent| and |children| to each other.
    *
    * @param {!Object} parent
    * @param {Array<Object>} children
    */
   setChildren: function(parent, children) {
     // Connect parent to its children.
     parent.children = children;
     parent.firstChild = children[0];
     parent.lastChild = children[children.length - 1];
 
     for (let i = 0; i < children.length; i++) {
       let child = children[i];
 
       // Connect children to their parent.
       child.parent = parent;
 
       // Connect children to each other
       if (i < children.length - 1)
         child.nextSibling = children[i + 1];
       if (i > 0)
         child.previousSibling = children[i - 1];
     }
   },
 };