md-settings: wrap lock screen dialogs in dom-if.

chrome/browser/resources/settings/people_page/fingerprint_list.js

Index: chrome/browser/resources/settings/people_page/fingerprint_list.js
diff --git a/chrome/browser/resources/settings/people_page/fingerprint_list.js b/chrome/browser/resources/settings/people_page/fingerprint_list.js
index 442c53cc2187584284fe732e2a87b0770160d047..54e76257b7735ee334578f002ea6a17b813b0cb8 100644
--- a/chrome/browser/resources/settings/people_page/fingerprint_list.js
+++ b/chrome/browser/resources/settings/people_page/fingerprint_list.js
@@ -31,7 +31,10 @@ Polymer({
       value: function() {
         return [];
       }
-    }
+    },
+
+    /** @private */
+    showSetupFingerprintDialog_: Boolean,
   },
 
   /** @private {?settings.FingerprintBrowserProxy} */
@@ -145,11 +148,17 @@ Polymer({
    * @private
    */
   openAddFingerprintDialog_: function() {
-    this.$.setupFingerprint.open();
+    this.showSetupFingerprintDialog_ = true;
+    this.async(function() {
+      var dialog = this.$$('settings-setup-fingerprint-dialog');
+      dialog.addEventListener('close',
+          this.onSetupFingerprintDialogClose_.bind(this));

[stevenjb, 2017/06/01 17:28:24]

Instead of this, does this work in the HTML for the dialog:

on-close="[[onSetupFingerprintDialogClose_]]"

?

[dpapad, 2017/06/01 17:48:44]

+1. We've been following the on-close= approach in the majority of cases.

[sammiequon, 2017/06/01 20:21:10]

Done.

+    }.bind(this));
   },
 
   /** @private */
   onSetupFingerprintDialogClose_: function() {
+    this.showSetupFingerprintDialog_ = false;
     cr.ui.focusWithoutInk(assert(this.$$('#addFingerprint')));
     this.browserProxy_.startAuthentication();
   },
@@ -162,7 +171,7 @@ Polymer({
   onScreenLocked_: function(screenIsLocked) {
     if (!screenIsLocked &&
         settings.getCurrentRoute() == settings.Route.FINGERPRINT) {
-      this.$.setupFingerprint.close();
+      this.onSetupFingerprintDialogClose_();
     }
   },
 });