WebUI Prefs: Don't use display:block for labels

chrome/browser/resources/options/advanced_options.css

 /*
  * 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.
  */
 
 #advancedPage .informational-text {
   color: grey;
 }
 
-#advancedPage > section > div:only-of-type > label.checkbox {
+#advancedPage > section > div:only-of-type > div.checkbox {
   margin: 10px 0;
 }
 
 #advancedPage .section-group {
   margin: 10px 0;
 }
 
 #advancedPage select,
 #advancedPage .web-content-select-label {
   min-width: 145px;
@@ skipping 11 matching lines @@
 
 #promptForDownload {
   margin-bottom: 10px;
 }
 
 #fontSettingsCustomizeFontsButton,
 #gearSettingsConfigureGearsButton,
 #privacyClearDataButton {
   margin-left: 10px;
 }