[MD settings] replace secondary-action with separator

chrome/browser/resources/settings/site_settings/site_list.html

 <link rel="import" href="chrome://resources/html/polymer.html">
 <link rel="import" href="chrome://resources/cr_elements/cr_action_menu/cr_action_menu.html">
 <link rel="import" href="chrome://resources/cr_elements/icons.html">
 <link rel="import" href="chrome://resources/cr_elements/policy/cr_policy_pref_indicator.html">
 <link rel="import" href="chrome://resources/html/web_ui_listener_behavior.html">
 <link rel="import" href="chrome://resources/polymer/v1_0/iron-flex-layout/iron-flex-layout-classes.html">
 <link rel="import" href="chrome://resources/polymer/v1_0/iron-icon/iron-icon.html">
 <link rel="import" href="chrome://resources/polymer/v1_0/paper-icon-button/paper-icon-button.html">
 <link rel="import" href="../i18n_setup.html">
 <link rel="import" href="../icons.html">
@@ skipping 63 matching lines @@
                 <!-- This div must not contain extra whitespace. -->
                 <div class="selectable secondary text-elide"
                     id="siteDescription">[[computeSiteDescription_(item)]]</div>
               </div>
               <template is="dom-if" if="[[enableSiteSettings_]]">
                 <div on-tap="onOriginTap_" actionable>
                   <button class="subpage-arrow" is="paper-icon-button-light"
                       aria-label$="[[item.displayName]]"
                       aria-describedby="siteDescription"></button>
                 </div>
-                <!-- This div is intentionally empty. It creates a vertical grey
-                     bar. This can be merged into the html that follows this
-                     template after the |enableSiteSettings_| is removed. -->
-                <div class="secondary-action"></div>
+                <div class="separator"></div>
               </template>
             </div>
             <template is="dom-if" if="[[item.controlledBy]]">
               <cr-policy-pref-indicator pref="[[item]]"
                   icon-aria-label="[[label]]">
               </cr-policy-pref-indicator>
             </template>
 
             <paper-icon-button id="resetSite" icon="cr:delete"
                 hidden="[[isResetButtonHidden_(
@@ skipping 11 matching lines @@
       </div>
     </div>
     <template is="dom-if" if="[[showEditExceptionDialog_]]" restamp>
       <settings-edit-exception-dialog model="[[actionMenuSite_]]"
           on-close="onEditExceptionDialogClosed_">
       </settings-edit-exception-dialog>
     </template>
   </template>
   <script src="site_list.js"></script>
 </dom-module>