Reland "Enable powerwash shortcut in views-based login screen."

This reverts commit 14fd238a.
Removes the chrome.send('showAddUser') in md_login.js to avoid a race
between the powerwash dialog and the Gaia signin screen.

Bug: 837501
Cq-Include-Trybots: luci.chromium.try:closure_compilation
Change-Id: I7ab656ebe522cbd164073b73b3dd927cca7b1f13
Reviewed-on: https://chromium-review.googlesource.com/1129384
Commit-Queue: Quan Nguyen <qnnguyen@chromium.org>
Reviewed-by: Jacob Dufault <jdufault@chromium.org>
Reviewed-by: Dan Erat <derat@chromium.org>
Reviewed-by: Daniel Cheng <dcheng@chromium.org>
Cr-Commit-Position: refs/heads/master@{#576306}

ash/login/login_screen_controller.cc

@@ -237,6 +237,12 @@ void LoginScreenController::ShowFeedback() {
   login_screen_client_->ShowFeedback();
 }
 
+void LoginScreenController::ShowResetScreen() {
+  if (!login_screen_client_)
+    return;
+  login_screen_client_->ShowResetScreen();
+}
+
 void LoginScreenController::AddObserver(
     LoginScreenControllerObserver* observer) {
   observers_.AddObserver(observer);

ash/login/login_screen_controller.h

@@ -82,6 +82,7 @@ class ASH_EXPORT LoginScreenController : public mojom::LoginScreen {
   void RequestPublicSessionKeyboardLayouts(const AccountId& account_id,
                                            const std::string& locale);
   void ShowFeedback();
+  void ShowResetScreen();
   void LaunchKioskApp(const std::string& app_id);
   void LaunchArcKioskApp(const AccountId& account_id);
 

ash/login/mock_login_screen_client.h

@@ -68,6 +68,7 @@ class MockLoginScreenClient : public mojom::LoginScreenClient {
   MOCK_METHOD2(RequestPublicSessionKeyboardLayouts,
                void(const AccountId& account_id, const std::string& locale));
   MOCK_METHOD0(ShowFeedback, void());
+  MOCK_METHOD0(ShowResetScreen, void());
   MOCK_METHOD1(LaunchKioskApp, void(const std::string& app_id));
   MOCK_METHOD1(LaunchArcKioskApp, void(const AccountId& account_id));
 

ash/login/ui/lock_contents_view.cc

@@ -38,10 +38,13 @@
 #include "chromeos/dbus/dbus_thread_manager.h"
 #include "components/user_manager/user_type.h"
 #include "ui/accessibility/ax_node_data.h"
+#include "ui/base/accelerators/accelerator.h"
 #include "ui/base/l10n/l10n_util.h"
 #include "ui/display/display.h"
 #include "ui/display/manager/display_manager.h"
 #include "ui/display/manager/managed_display_info.h"
+#include "ui/events/event_constants.h"
+#include "ui/events/keycodes/keyboard_codes.h"
 #include "ui/gfx/geometry/insets.h"
 #include "ui/gfx/geometry/rect.h"
 #include "ui/gfx/geometry/size.h"
@@ -1443,6 +1446,9 @@ void LockContentsView::RegisterAccelerators() {
       AcceleratorAction::kFocusNextUser;
   accel_map_[ui::Accelerator(ui::VKEY_LEFT, 0)] =
       AcceleratorAction::kFocusPreviousUser;
+  accel_map_[ui::Accelerator(
+      ui::VKEY_R, ui::EF_SHIFT_DOWN | ui::EF_ALT_DOWN | ui::EF_CONTROL_DOWN)] =
+      AcceleratorAction::kShowResetScreen;
 
   AcceleratorController* controller = Shell::Get()->accelerator_controller();
   for (const auto& item : accel_map_)
@@ -1460,6 +1466,9 @@ void LockContentsView::PerformAction(AcceleratorAction action) {
     case AcceleratorAction::kFocusPreviousUser:
       FocusPreviousUser();
       return;
+    case AcceleratorAction::kShowResetScreen:
+      Shell::Get()->login_screen_controller()->ShowResetScreen();
+      return;
     default:
       NOTREACHED();
   }

ash/login/ui/lock_contents_view.h

@@ -104,6 +104,7 @@ class ASH_EXPORT LockContentsView
     kShowFeedback,
     kFocusNextUser,
     kFocusPreviousUser,
+    kShowResetScreen,
   };
 
   // Number of login attempts before a login dialog is shown. For example, if

ash/login/ui/lock_contents_view_unittest.cc

@@ -35,6 +35,7 @@
 #include "testing/gtest/include/gtest/gtest.h"
 #include "ui/display/manager/display_manager.h"
 #include "ui/display/test/display_manager_test_api.h"
+#include "ui/events/event_constants.h"
 #include "ui/events/test/event_generator.h"
 #include "ui/gfx/geometry/rect.h"
 #include "ui/views/controls/textfield/textfield.h"
@@ -1722,4 +1723,15 @@ TEST_F(LockContentsViewKeyboardUnitTest, UserSwapFocusesBigView) {
   EXPECT_TRUE(login_views_utils::HasFocusInAnyChildView(primary_password_view));
 }
 
+TEST_F(LockContentsViewKeyboardUnitTest, PowerwashShortcutShowsResetScreen) {
+  ASSERT_NO_FATAL_FAILURE(ShowLoginScreen());
+  std::unique_ptr<MockLoginScreenClient> client = BindMockLoginScreenClient();
+  EXPECT_CALL(*client, ShowResetScreen()).Times(1);
+
+  ui::test::EventGenerator* generator = GetEventGenerator();
+  generator->PressKey(
+      ui::VKEY_R, ui::EF_CONTROL_DOWN | ui::EF_SHIFT_DOWN | ui::EF_ALT_DOWN);
+  base::RunLoop().RunUntilIdle();
+}
+
 }  // namespace ash

ash/public/interfaces/login_screen.mojom

@@ -226,6 +226,9 @@ interface LoginScreenClient {
   // Request to show a feedback report dialog in chrome.
   ShowFeedback();
 
+  // Show the reset (powerwash) screen.
+  ShowResetScreen();
+
   // Launch the specific kiosk app.
   LaunchKioskApp(string app_id);
 

chrome/browser/chromeos/login/screens/gaia_view.h

@@ -43,6 +43,10 @@ class GaiaView {
                                        const std::string& password,
                                        const std::string& services) = 0;
 
+  // Cancels the request to show the sign-in screen while the asynchronous
+  // clean-up process that precedes the screen being shown is in progress.
+  virtual void CancelShowGaiaAsync() = 0;
+
  private:
   DISALLOW_COPY_AND_ASSIGN(GaiaView);
 };

chrome/browser/chromeos/login/ui/login_display_host_mojo.cc

@@ -162,8 +162,10 @@ void LoginDisplayHostMojo::StartWizard(OobeScreen first_screen) {
   wizard_controller_ = std::make_unique<WizardController>();
   wizard_controller_->Init(first_screen);
 
-  // Post login screens should not be closable by escape key.
-  dialog_->Show(false /*closable_by_esc*/);
+  // Post login screens (aside from powerwash) should not be closable by escape
+  // key.
+  bool closable_by_esc = first_screen == OobeScreen::SCREEN_OOBE_RESET;
+  dialog_->Show(closable_by_esc);
 }
 
 WizardController* LoginDisplayHostMojo::GetWizardController() {
@@ -191,6 +193,14 @@ void LoginDisplayHostMojo::OnStartSignInScreen(
     return;
   }
 
+  if (signin_screen_started_) {
+    dialog_->Hide();
+    GetOobeUI()->GetGaiaScreenView()->ShowGaiaAsync(base::nullopt);
+    return;
+  }
+
+  signin_screen_started_ = true;
+
   existing_user_controller_ = std::make_unique<ExistingUserController>();
   login_display_->set_delegate(existing_user_controller_.get());
 
@@ -250,6 +260,11 @@ void LoginDisplayHostMojo::ShowGaiaDialog(
       GetOobeUI()->GetGaiaScreenView()->ShowGaiaAsync(prefilled_account);
     LoadWallpaper(*prefilled_account);
   } else {
+    // Restore the gaia screen if the OOBE dialog is currently occupied by a
+    // wizard.
+    if (GetOobeUI()->current_screen() != OobeScreen::SCREEN_GAIA_SIGNIN)
+      GetOobeUI()->GetGaiaScreenView()->ShowGaiaAsync(base::nullopt);
+
     LoadSigninWallpaper();
   }
 

chrome/browser/chromeos/login/ui/login_display_host_mojo.h

@@ -155,6 +155,11 @@ class LoginDisplayHostMojo : public LoginDisplayHostCommon,
   // Updates UI when version info is changed.
   std::unique_ptr<MojoVersionInfoDispatcher> version_info_updater_;
 
+  // Set to true on the first call to OnStartSignInScreen. Never reset to false.
+  // This is used to avoid doing redundant work (e.g. LockScreen::Show()) if the
+  // login screen is already showing and OnStartSignInScreen is called again.
+  bool signin_screen_started_ = false;
+
   base::WeakPtrFactory<LoginDisplayHostMojo> weak_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(LoginDisplayHostMojo);

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

@@ -69,9 +69,6 @@ cr.define('cr.ui.Oobe', function() {
       login.TopHeaderBar.decorate($('top-header-bar'));
 
       chrome.send('screenStateInitialize');
-
-      if (Oobe.getInstance().showingViewsLogin)
-        chrome.send('showAddUser');
     },
 
     // Dummy Oobe functions not present with stripped login UI.

chrome/browser/ui/ash/login_screen_client.cc

@@ -9,11 +9,13 @@
 #include "ash/public/interfaces/constants.mojom.h"
 #include "chrome/browser/chromeos/login/lock/screen_locker.h"
 #include "chrome/browser/chromeos/login/reauth_stats.h"
+#include "chrome/browser/chromeos/login/screens/gaia_view.h"
 #include "chrome/browser/chromeos/login/ui/login_display_host.h"
 #include "chrome/browser/chromeos/login/ui/user_adding_screen.h"
 #include "chrome/browser/profiles/profile_metrics.h"
 #include "chrome/browser/ui/ash/wallpaper_controller_client.h"
 #include "chrome/browser/ui/webui/chromeos/login/l10n_util.h"
+#include "chrome/browser/ui/webui/chromeos/login/oobe_ui.h"
 #include "components/user_manager/remove_user_delegate.h"
 #include "content/public/common/service_manager_connection.h"
 #include "services/service_manager/public/cpp/connector.h"
@@ -151,6 +153,19 @@ void LoginScreenClient::ShowFeedback() {
     chromeos::LoginDisplayHost::default_host()->ShowFeedback();
 }
 
+void LoginScreenClient::ShowResetScreen() {
+  if (chromeos::LoginDisplayHost::default_host()->GetOobeUI()) {
+    // If gaia init is in progress, cancel it so the screen doesn't race with
+    // the reset wizard.
+    chromeos::LoginDisplayHost::default_host()
+        ->GetOobeUI()
+        ->GetGaiaScreenView()
+        ->CancelShowGaiaAsync();
+    chromeos::LoginDisplayHost::default_host()->StartWizard(
+        chromeos::OobeScreen::SCREEN_OOBE_RESET);
+  }
+}
+
 void LoginScreenClient::LaunchKioskApp(const std::string& app_id) {
   chromeos::LoginDisplayHost::default_host()->StartAppLaunch(app_id, false,
                                                              false);

chrome/browser/ui/ash/login_screen_client.h

@@ -83,6 +83,7 @@ class LoginScreenClient : public ash::mojom::LoginScreenClient {
   void RequestPublicSessionKeyboardLayouts(const AccountId& account_id,
                                            const std::string& locale) override;
   void ShowFeedback() override;
+  void ShowResetScreen() override;
   void LaunchKioskApp(const std::string& app_id) override;
   void LaunchArcKioskApp(const AccountId& account_id) override;
 

chrome/browser/ui/webui/chromeos/login/gaia_screen_handler.cc

@@ -829,7 +829,6 @@ void GaiaScreenHandler::HandleShowAddUser(const base::ListValue* args) {
   TRACE_EVENT_ASYNC_STEP_INTO0("ui", "ShowLoginWebUI",
                                LoginDisplayHostWebUI::kShowLoginWebUIid,
                                "ShowAddUser");
-
   std::string email;
   // |args| can be null if it's OOBE.
   if (args)
@@ -837,6 +836,7 @@ void GaiaScreenHandler::HandleShowAddUser(const base::ListValue* args) {
   set_populated_email(email);
   if (!email.empty())
     SendReauthReason(AccountId::FromUserEmail(email));
+
   OnShowAddUser();
 }
 

chrome/browser/ui/webui/chromeos/login/gaia_screen_handler.h

@@ -56,6 +56,7 @@ class GaiaScreenHandler : public BaseScreenHandler,
   void ShowSigninScreenForTest(const std::string& username,
                                const std::string& password,
                                const std::string& services) override;
+  void CancelShowGaiaAsync() override;
 
  private:
   // TODO (xiaoyinh): remove this dependency.
@@ -171,10 +172,6 @@ class GaiaScreenHandler : public BaseScreenHandler,
   // principals API was used during SAML login.
   void SetSAMLPrincipalsAPIUsed(bool api_used);
 
-  // Cancels the request to show the sign-in screen while the asynchronous
-  // clean-up process that precedes the screen showing is in progress.
-  void CancelShowGaiaAsync();
-
   // Shows signin screen after dns cache and cookie cleanup operations finish.
   void ShowGaiaScreenIfReady();