MD Settings: Certificate manager, respect USE_NSS_CERTS.

chrome/browser/resources/settings/privacy_page/privacy_page.js

 // Copyright 2015 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.
 
 /**
  * @fileoverview
  * 'settings-privacy-page' is the settings page containing privacy and
  * security settings.
  *
  * Example:
@@ skipping 24 matching lines @@
       notify: true,
     },
   },
 
   ready: function() {
     this.ContentSettingsTypes = settings.ContentSettingsTypes;
   },
 
   /** @private */
   onManageCertificatesTap_: function() {
+<if expr="use_nss_certs">
     this.$.pages.setSubpageChain(['manage-certificates']);
+</if>
+<if expr="not use_nss_certs">
+    // TODO(dpapad): Launch native certificate manager here.
+</if>
   },
 
   /** @private */
   onSiteSettingsTap_: function() {
     this.$.pages.setSubpageChain(['site-settings']);
   },
 
   /** @private */
   onClearBrowsingDataTap_: function() {
     this.$.pages.querySelector('settings-clear-browsing-data-dialog').open();
   },
 });