MD Settings: Certificate manager, polish "no certificates" text.

chrome/browser/resources/settings/certificate_manager_page/certificate_list.js

 // Copyright 2016 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-certificate-list' is an element that displays a list
  * of certificates.
  */
 Polymer({
   is: 'settings-certificate-list',
 
   properties: {
     /** @type {!Array<!Certificate>} */
     certificates: {
       type: Array,
       value: function() { return []; },
     },
 
     /** @type {!settings.CertificateType} */
     certificateType: String,
   },
 
   behaviors: [I18nBehavior],
 
   /**
    * @return {string}
    * @private
    */
   getDescription_: function() {
+    if (this.certificates.length == 0)
+      return this.i18n('certificateManagerNoCertificates');
+
     switch (this.certificateType) {
       case settings.CertificateType.PERSONAL:
         return this.i18n('certificateManagerYourCertificatesDescription');
       case settings.CertificateType.SERVER:
         return this.i18n('certificateManagerServersDescription');
       case settings.CertificateType.CA:
         return this.i18n('certificateManagerAuthoritiesDescription');
       case settings.CertificateType.OTHER:
         return this.i18n('certificateManagerOthersDescription');
     }
@@ skipping 55 matching lines @@
           }.bind(this),
           this.onRejected_.bind(this));
     } else if (this.certificateType == settings.CertificateType.SERVER) {
       browserProxy.importServerCertificate().catch(
           this.onRejected_.bind(this));
     } else {
       assertNotReached();
     }
   },
 });