[cros] Login screen: 'Create user' link hidden when BWSI is disabled.

Also: login screen listens for device policy changes and updates links accordingly.


BUG=chromium-os:23664
TEST=Manual: see bug description.


Review URL: http://codereview.chromium.org/9046005

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@116047 0039d316-1c4b-4281-b951-d872f2087c98

3 files changed, 77 insertions, 11 deletions

diff --git a/chrome/browser/resources/chromeos/login/screen_gaia_signin.js b/chrome/browser/resources/chromeos/login/screen_gaia_signin.js
index 57b6869..bfc702f 100644
--- a/chrome/browser/resources/chromeos/login/screen_gaia_signin.js
+++ b/chrome/browser/resources/chromeos/login/screen_gaia_signin.js
@@ -141,11 +141,15 @@ cr.define('login', function() {
       document.removeEventListener('focusout', listener);
     },
 
+    /**
+     * Loads the authentication extension into the iframe.
+     * @param {Object} data Extension parameters bag.
+     * @private
+     */
     loadAuthExtension_: function(data) {
       this.silentLoad_ = data.silentLoad;
 
-      $('createAccount').hidden = !data.createAccount;
-      $('guestSignin').hidden = !data.guestSignin;
+      this.updateAuthExtension_(data);
 
       var params = [];
       if (data.gaiaOrigin)
@@ -190,6 +194,16 @@ cr.define('login', function() {
     },
 
     /**
+     * Updates the authentication extension with new parameters, if needed.
+     * @param {Object} data New extension parameters bag.
+     * @private
+     */
+    updateAuthExtension_: function(data) {
+      $('createAccount').hidden = !data.createAccount;
+      $('guestSignin').hidden = !data.guestSignin;
+    },
+
+    /**
      * Checks if message comes from the loaded authentication extension.
      * @param e {object} Payload of the received HTML5 message.
      * @type {bool}
@@ -306,10 +320,22 @@ cr.define('login', function() {
     }
   };
 
+  /**
+   * Loads the authentication extension into the iframe.
+   * @param {Object} data Extension parameters bag.
+   */
   GaiaSigninScreen.loadAuthExtension = function(data) {
     $('gaia-signin').loadAuthExtension_(data);
   };
 
+  /**
+   * Updates the authentication extension with new parameters, if needed.
+   * @param {Object} data New extension parameters bag.
+   */
+  GaiaSigninScreen.updateAuthExtension = function(data) {
+    $('gaia-signin').updateAuthExtension_(data);
+  };
+
   return {
     GaiaSigninScreen: GaiaSigninScreen
   };
diff --git a/chrome/browser/ui/webui/chromeos/login/signin_screen_handler.cc b/chrome/browser/ui/webui/chromeos/login/signin_screen_handler.cc
index dfa05e9..e1ea228 100644
--- a/chrome/browser/ui/webui/chromeos/login/signin_screen_handler.cc
+++ b/chrome/browser/ui/webui/chromeos/login/signin_screen_handler.cc
@@ -88,6 +88,23 @@ void ClearDnsCache(IOThread* io_thread) {
 
 namespace chromeos {
 
+namespace {
+
+// Updates params dictionary passed to the auth extension with related
+// preferences from CrosSettings.
+void UpdateAuthParamsFromSettings(DictionaryValue* params,
+                                  const CrosSettings* cros_settings) {
+  bool allow_new_user = true;
+  cros_settings->GetBoolean(kAccountsPrefAllowNewUser, &allow_new_user);
+  bool allow_guest = true;
+  cros_settings->GetBoolean(kAccountsPrefAllowGuest, &allow_guest);
+  // Account creation depends on Guest sign-in (http://crosbug.com/24570).
+  params->SetBoolean("createAccount", allow_new_user && allow_guest);
+  params->SetBoolean("guestSignin", allow_guest);
+}
+
+} //  namespace
+
 // Class which observes network state changes and calls registered callbacks.
 // State is considered changed if connection or the active network has been
 // changed. Also, it answers to the requests about current network state.
@@ -236,6 +253,8 @@ SigninScreenHandler::SigninScreenHandler()
       cookie_remover_(NULL),
       ALLOW_THIS_IN_INITIALIZER_LIST(weak_factory_(this)),
       key_event_listener_(NULL) {
+  CrosSettings::Get()->AddSettingsObserver(kAccountsPrefAllowNewUser, this);
+  CrosSettings::Get()->AddSettingsObserver(kAccountsPrefAllowGuest, this);
 }
 
 SigninScreenHandler::~SigninScreenHandler() {
@@ -244,6 +263,8 @@ SigninScreenHandler::~SigninScreenHandler() {
     cookie_remover_->RemoveObserver(this);
   if (key_event_listener_)
     key_event_listener_->RemoveCapsLockObserver(this);
+  CrosSettings::Get()->RemoveSettingsObserver(kAccountsPrefAllowNewUser, this);
+  CrosSettings::Get()->RemoveSettingsObserver(kAccountsPrefAllowGuest, this);
 }
 
 void SigninScreenHandler::GetLocalizedStrings(
@@ -461,6 +482,15 @@ void SigninScreenHandler::OnCapsLockChange(bool enabled) {
   }
 }
 
+void SigninScreenHandler::Observe(int type,
+                                  const content::NotificationSource& source,
+                                  const content::NotificationDetails& details) {
+  if (type == chrome::NOTIFICATION_SYSTEM_SETTING_CHANGED)
+    UpdateAuthExtension();
+  else
+    NOTREACHED();
+}
+
 void SigninScreenHandler::OnDnsCleared() {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
   dns_clear_task_running_ = false;
@@ -491,14 +521,7 @@ void SigninScreenHandler::LoadAuthExtension(bool force, bool silent_load) {
   params.SetString("email", email_);
   email_.clear();
 
-  // TODO(pastarmovj): Watch for changes of this variables to update the UI
-  // properly when the policy has been fetched on sign-on screen.
-  bool allow_new_user = true;
-  CrosSettings::Get()->GetBoolean(kAccountsPrefAllowNewUser, &allow_new_user);
-  params.SetBoolean("createAccount", allow_new_user);
-  bool allow_guest = true;
-  CrosSettings::Get()->GetBoolean(kAccountsPrefAllowGuest, &allow_guest);
-  params.SetBoolean("guestSignin", allow_guest);
+  UpdateAuthParamsFromSettings(&params, CrosSettings::Get());
 
   const std::string app_locale = g_browser_process->GetApplicationLocale();
   if (!app_locale.empty())
@@ -522,6 +545,12 @@ void SigninScreenHandler::LoadAuthExtension(bool force, bool silent_load) {
                                    params);
 }
 
+void SigninScreenHandler::UpdateAuthExtension() {
+  DictionaryValue params;
+  UpdateAuthParamsFromSettings(&params, CrosSettings::Get());
+  web_ui_->CallJavascriptFunction("login.GaiaSigninScreen.updateAuthExtension",
+                                  params);
+}
 
 void SigninScreenHandler::ShowSigninScreenForCreds(
     const std::string& username,
diff --git a/chrome/browser/ui/webui/chromeos/login/signin_screen_handler.h b/chrome/browser/ui/webui/chromeos/login/signin_screen_handler.h
index b974158..bb49f7e 100644
--- a/chrome/browser/ui/webui/chromeos/login/signin_screen_handler.h
+++ b/chrome/browser/ui/webui/chromeos/login/signin_screen_handler.h
@@ -17,6 +17,7 @@
 #include "chrome/browser/chromeos/system_key_event_listener.h"
 #include "chrome/browser/ui/webui/chromeos/login/base_screen_handler.h"
 #include "content/browser/webui/web_ui.h"
+#include "content/public/browser/notification_observer.h"
 
 class BrowsingDataRemover;
 
@@ -105,7 +106,8 @@ class SigninScreenHandlerDelegate {
 class SigninScreenHandler : public BaseScreenHandler,
                             public LoginDisplayWebUIHandler,
                             public BrowsingDataRemover::Observer,
-                            public SystemKeyEventListener::CapsLockObserver {
+                            public SystemKeyEventListener::CapsLockObserver,
+                            public content::NotificationObserver {
  public:
   SigninScreenHandler();
   virtual ~SigninScreenHandler();
@@ -148,6 +150,11 @@ class SigninScreenHandler : public BaseScreenHandler,
   // SystemKeyEventListener::CapsLockObserver overrides.
   virtual void OnCapsLockChange(bool enabled) OVERRIDE;
 
+  // content::NotificationObserver implementation.
+  virtual void Observe(int type,
+                       const content::NotificationSource& source,
+                       const content::NotificationDetails& details) OVERRIDE;
+
   // Shows signin screen after dns cache and cookie cleanup operations finish.
   void ShowSigninScreenIfReady();
 
@@ -157,6 +164,10 @@ class SigninScreenHandler : public BaseScreenHandler,
   // shouldn't grab the focus.
   void LoadAuthExtension(bool force, bool silent_load);
 
+  // Updates authentication extension. Called when device settings that affect
+  // sign-in (allow BWSI and allow whitelist) are changed.
+  void UpdateAuthExtension();
+
   // Handles confirmation message of user authentication that was performed by
   // the authentication extension.
   void HandleCompleteLogin(const base::ListValue* args);