Clear the login webview when SAML flow is canceled

chrome/browser/resources/chromeos/login/screen_gaia_signin.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.
 
 /**
  * @fileoverview Oobe signin screen implementation.
  */
 
 login.createScreen('GaiaSigninScreen', 'gaia-signin', function() {
   // GAIA animation guard timer. Started when GAIA page is loaded
@@ skipping 905 matching lines @@
     },
 
     /**
      * Clears input fields and switches to input mode.
      * @param {boolean} takeFocus True to take focus.
      * @param {boolean} forceOnline Whether online sign-in should be forced.
      * If |forceOnline| is false previously used sign-in type will be used.
      */
     reset: function(takeFocus, forceOnline) {
       // Reload and show the sign-in UI if needed.
-      this.gaiaAuthHost_.resetStates_();
+      this.gaiaAuthHost_.reload();

[emaxx, 2016/05/19 19:02:16]

Authenticator.prototype.reload does the same as
Authenticator.prototype.resetStates_, but additionally resets the webview URL to
the initial one.
(Not sure why the reload method was not used here initially.)


Achuith, am I correct that the initial URL is always pointing to a Google-owned
page, so that it's safe to leave the webview with it opened in the background?

[xiyuan, 2016/05/19 22:47:08]

We have a policy to make Gaia auto redirect to saml idp. And if that policy is
enabled and our saml idp is using webcam, this change would not really fix the
problem.

[afakhry, 2016/05/20 00:14:21]

Authenticator.prototype.reload() doesn't reset the GAIA sign in screen. It will
assign webview_.src to the same reloadUrl_ that was most recently calculated in
the most recent load().

Calling reload() here will reload the same SAML IdP Url again in the Webview
(assuming the previous load() loaded that SAML IdP page). I suggest (as xiyuan
mention on the bug thread) to keep using resetStates_(); but modify it to reset
webview_.src to some default URL, say about:blank or something.

[emaxx, 2016/05/23 15:00:48]

OK, restored this back to calling resetStates_. And added into resetStates_ the
redirection of webview to 'about:blank'.

       if (takeFocus) {
         if (!forceOnline && this.isOffline()) {
           // Show 'Cancel' button to allow user to return to the main screen
           // (e.g. this makes sense when connection is back).
           Oobe.getInstance().headerHidden = false;
           $('login-header-bar').signinUIState = SIGNIN_UI_STATE.GAIA_SIGNIN;
           // Do nothing, since offline version is reloaded after an error comes.
         } else {
           Oobe.showSigninUI();
         }
@@ skipping 103 matching lines @@
       this.classList.toggle('whitelist-error', show);
       this.loading = !show;
 
       if (!show)
         Oobe.showSigninUI();
 
       this.updateControlsState();
     }
   };
 });