Migrate <cr-dialog> from PaperDialogBehavior to native <dialog>.

chrome/browser/resources/settings/certificate_manager_page/ca_trust_edit_dialog.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-ca-trust-edit-dialog' allows the user to
  *  - specify the trust level of a certificate authority that is being
  *    imported.
  *  - edit the trust level of an already existing certificate authority.
  */
@@ skipping 24 matching lines @@
     this.explanationText_ = loadTimeData.getStringF(
         'certificateManagerCaTrustEditDialogExplanation',
         this.model.name);
 
     // A non existing |model.id| indicates that a new certificate is being
     // imported, otherwise an existing certificate is being edited.
     if (this.model.id) {
       this.browserProxy_.getCaCertificateTrust(this.model.id).then(
           /** @param {!CaTrustInfo} trustInfo */
           function(trustInfo) {
+            if (!this.isAttached) {
+              // This element might have been detached from the DOM during the
+              // async operation (happens in testing code). Do not attempt to
+              // open the dialog in such case.
+              return;

[Dan Beam, 2016/07/26 23:36:12]

shouldn't we propagate trustInfo_ though?

[dpapad, 2016/07/27 01:21:47]

I ended up removing this completely, by making the test smarter such as it waits
for showModal() to be called before moving on to the next test (using
MutationObserver for the 'open' attribute). This is better because this code no
longer runs after the test that created this dialog has finished, instead it
runs as part of the test.

+            }
+
             this.trustInfo_ = trustInfo;
-            this.$.dialog.open();
+            this.$.dialog.showModal();
           }.bind(this));
     } else {
-      /** @type {!CrDialogElement} */ (this.$.dialog).open();
+      /** @type {!CrDialogElement} */ (this.$.dialog).showModal();
     }
   },
 
   /** @private */
   onCancelTap_: function() {
     /** @type {!CrDialogElement} */ (this.$.dialog).close();
   },
 
   /** @private */
   onOkTap_: function() {
@@ skipping 10 matching lines @@
       this.$.spinner.active = false;
       /** @type {!CrDialogElement} */ (this.$.dialog).close();
     }.bind(this),
     /** @param {!CertificatesError} error */
     function(error) {
       /** @type {!CrDialogElement} */ (this.$.dialog).close();
       this.fire('certificates-error', error);
     }.bind(this));
   },
 });