certificate manager: Disable export option for TPM-backed certs.

chrome/browser/resources/options2/certificate_manager.js

 // Copyright (c) 2012 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.
 
 cr.define('options', function() {
   var OptionsPage = options.OptionsPage;
 
   /////////////////////////////////////////////////////////////////////////////
   // CertificateManagerTab class:
 
@@ skipping 98 matching lines @@
   CertificateManagerTab.prototype = {
 
     /**
      * Update button state.
      * @private
      * @param {!Object} data The data of the selected item.
      */
     updateButtonState: function(data) {
       var isCert = !!data && data.id.substr(0, 5) == 'cert-';
       var readOnly = !!data && data.readonly;
+      var extractable = !!data && data.extractable;
       var hasChildren = this.tree.items.length > 0;
       this.viewButton.disabled = !isCert;
       if (this.editButton !== null)
         this.editButton.disabled = !isCert;
       if (this.backupButton !== null)
-        this.backupButton.disabled = !isCert;
+        this.backupButton.disabled = !isCert || !extractable;
       if (this.backupAllButton !== null)
         this.backupAllButton.disabled = !hasChildren;
       if (this.exportButton !== null)
         this.exportButton.disabled = !isCert;
       this.deleteButton.disabled = !isCert || readOnly;
     },
 
     /**
      * Handles certificate tree selection change.
      * @private
@@ skipping 110 matching lines @@
         tpmPollingTimer = window.setTimeout(checkTpmToken, 5000);
     }
   };
 
   // Export
   return {
     CertificateManagerTab: CertificateManagerTab,
     CertificateManager: CertificateManager
   };
 });