[cros,login] Restore the focus after hidden auth extension has grabbed it.

chrome/browser/resources/chromeos/login/screen_gaia_signin.js

 // Copyright (c) 2011 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.
  */
 
 cr.define('login', function() {
 
@@ skipping 12 matching lines @@
     GaiaSigninScreen.decorate(screen);
     Oobe.getInstance().registerScreen(screen);
     window.addEventListener('message',
                             screen.onMessage_.bind(screen), false);
   };
 
   GaiaSigninScreen.prototype = {
     __proto__: HTMLDivElement.prototype,
 
     // Authentication extension's start page URL.
-    extension_url_: null,
+    extensionUrl_: null,
+
+    // Whether extension should be loaded silently.
+    silentLoad_: false,
+
+    // Whether there is focused element.
+    hasFocused_: false,
 
     // Number of times that we reload extension frame.
     retryCount_: 0,
 
     // Timer id of pending retry.
     retryTimer_: undefined,
 
     /** @inheritDoc */
     decorate: function() {
+      this.frame_ = $('signin-frame');
+
       $('createAccount').innerHTML = localStrings.getStringF(
           'createAccount',
           '<a id="createAccountLink" class="signin-link" href="#">',
           '</a>');
       $('guestSignin').innerHTML = localStrings.getStringF(
           'guestSignin',
           '<a id="guestSigninLink" class="signin-link" href="#">',
           '</a>');
       $('createAccountLink').onclick = function() {
         chrome.send('createAccount');
       };
       $('guestSigninLink').onclick = function() {
         chrome.send('launchIncognito');
       };
+      document.addEventListener(
+          'focusin', this.selfBind_(this.onFocusIn_.bind(this)));
     },
 
     /**
      * Header text of the screen.
      * @type {string}
      */
     get header() {
       return localStrings.getString('signinScreenTitle');
     },
 
     /**
      * Shows/hides loading UI.
      * @param {boolean} show True to show loading UI.
      * @private
      */
     showLoadingUI_: function(show) {
       $('gaia-loading').hidden = !show;
-      $('signin-frame').hidden = show;
+      this.frame_.hidden = show;
 
       // Sign-in right panel is hidden if all its items are hidden.
       $('signin-right').hidden = show ||
           ($('createAccount').hidden && $('guestSignin').hidden);
     },
 
     /**
      * Whether Gaia is loading.
      * @type {boolean}
      */
@@ skipping 15 matching lines @@
     onBeforeShow: function(data) {
       // Announce the name of the screen, if accessibility is on.
       $('gaia-signin-aria-label').setAttribute(
           'aria-label', localStrings.getString('signinScreenTitle'));
 
       // Button header is always visible when sign in is presented.
       // Header is hidden once GAIA reports on successful sign in.
       Oobe.getInstance().headerHidden = false;
     },
 
-    setExtensionUrl_: function(data) {
+    /**
+     * Returns function which gets an event and passes it and self to listener.
+     * @param {!Object} listener Listener to be wrapped.
+     */
+    selfBind_: function(listener) {
+      var selfBinded = function(e) {
+        listener(e, selfBinded);
+      }
+      return selfBinded;
+    },
+
+    /**
+     * Tracks first focus in event.
+     * @param {!Object} e Focus in event.
+     * @param {!Object} listener Listener which shold be removed from event
+     *   listeners list.
+     */
+    onFocusIn_: function(e, listener) {
+      this.hasFocused_ = true;
+      document.removeEventListener('focusin', listener);
+    },
+
+    /**
+     * Restore focus back to the focused element.
+     * @param {!Object} e Focus out event.
+     * @param {!Object} listener Listener which shold be removed from event
+     *   listeners list.
+     */
+    onFocusOut_: function(e, listener) {
+      window.setTimeout(e.target.focus.bind(e.target), 0);
+      document.removeEventListener('focusout', listener);
+    },
+
+    loadAuthExtension_: function(data) {
+      this.silentLoad_ = data.silentLoad;
+
       $('createAccount').hidden = !data.createAccount;
       $('guestSignin').hidden = !data.guestSignin;
 
       var params = [];
       if (data.gaiaOrigin)
         params.push('gaiaOrigin=' + encodeURIComponent(data.gaiaOrigin));
       if (data.hl)
         params.push('hl=' + encodeURIComponent(data.hl));
       if (data.email)
         params.push('email=' + encodeURIComponent(data.email));
       if (data.test_email)
         params.push('test_email=' + encodeURIComponent(data.test_email));
       if (data.test_password)
         params.push('test_password=' + encodeURIComponent(data.test_password));
 
       var url = data.startUrl;
       if (params.length)
         url += '?' + params.join('&');
 
-      if (data.forceReload || this.extension_url_ != url) {
+      if (data.forceReload || this.extensionUrl_ != url) {
         console.log('Opening extension: ' + data.startUrl +
                     ', opt_email=' + data.email);
 
-        $('signin-frame').src = url;
-        this.extension_url_ = url;
+        this.frame_.src = url;
+        this.extensionUrl_ = url;
 
         this.loading = true;
         this.clearRetry_();
       } else if (this.loading) {
         // Probably an error has occurred, so trying to reload.
         this.doReload();
       }
     },
 
     /**
      * Checks if message comes from the loaded authentication extension.
      * @param e {object} Payload of the received HTML5 message.
      * @type {bool}
      */
     isAuthExtMessage_: function(e) {
-      return this.extension_url_ != null &&
-          this.extension_url_.indexOf(e.origin) == 0 &&
-          e.source == $('signin-frame').contentWindow;
+      return this.extensionUrl_ != null &&
+          this.extensionUrl_.indexOf(e.origin) == 0 &&
+          e.source == this.frame_.contentWindow;
     },
 
     /**
      * Event handler that is invoked when HTML5 message is received.
      * @param e {object} Payload of the received HTML5 message.
      */
     onMessage_: function(e) {
       var msg = e.data;
       if (msg.method == 'completeLogin' && this.isAuthExtMessage_(e)) {
         chrome.send('completeLogin', [msg.email, msg.password] );
         this.loading = true;
         // Now that we're in logged in state header should be hidden.
         Oobe.getInstance().headerHidden = true;
       } else if (msg.method == 'loginUILoaded' && this.isAuthExtMessage_(e)) {
+        // TODO(altimofeev): there is no guarantee that next 'focusout' event
+        // will be caused by the extension, so better approach is direct asking
+        // the extension (and gaia consequently) to not grab the focus.
+        if (this.silentLoad_ && this.hasFocused_) {
+          document.addEventListener(
+              'focusout', this.selfBind_(this.onFocusOut_.bind(this)));
+        }
         $('error-message').update();
         this.loading = false;
         this.clearRetry_();
         chrome.send('loginWebuiReady');
       }
     },
 
     /**
      * Clears input fields and switches to input mode.
      * @param {boolean} takeFocus True to take focus.
@@ skipping 14 matching lines @@
         window.clearTimeout(this.retryTimer_);
         this.retryTimer_ = undefined;
       }
     },
 
     /**
      * Reloads extension frame.
      */
     doReload: function() {
       console.log('Reload auth extension frame.');
-      $('signin-frame').src = this.extension_url_;
+      this.frame_.src = this.extensionUrl_;
       this.retryTimer_ = undefined;
     },
 
     /**
      * Schedules extension frame reload.
      */
     scheduleRetry: function() {
       if (this.retryCount_ >= 3 || this.retryTimer_)
         return;
 
       const MAX_DELAY = 7200;  // 7200 seconds (i.e. 2 hours)
       const MIN_DELAY = 1;  // 1 second
 
       var delay = Math.pow(2, this.retryCount_) * 5;
       delay = Math.max(MIN_DELAY, Math.min(MAX_DELAY, delay)) * 1000;
 
       ++this.retryCount_;
       this.retryTimer_ = window.setTimeout(this.doReload.bind(this), delay);
       console.log('GaiaSigninScreen scheduleRetry in ' + delay + 'ms.');
     }
   };
 
-  GaiaSigninScreen.setExtensionUrl = function(data) {
-    $('gaia-signin').setExtensionUrl_(data);
+  GaiaSigninScreen.loadAuthExtension = function(data) {
+    $('gaia-signin').loadAuthExtension_(data);
   };
 
   return {
     GaiaSigninScreen: GaiaSigninScreen
   };
 });