[Autofill Auth UI] Reusing webauthn touch id dialog

Create new classes of WebauthnOfferDialog (view, controller, delegate).

Reusing AuthenticatorRequestSheetView for the detailed contents in
the dialog as required.
Mock: https://docs.google.com/presentation/d/16gfVy4EJ0hPibnOWZ8pqMF09Uy6uCWW2mCd1et9ILDw/edit#slide=id.g5dd211cc3b_0_67

This change is protected by experiment flag
kAutofillCreditCardAuthentication that if flag is disabled, the |
offer_fido_opt_in| in CreditCardAccessManager will always be false.

Browser tests will be added once the flow is complete and testable. This
is a base CL introducing the dialog.

Bug: 991037
Change-Id: Ie496b71c353cc20751adc290a5c83a82fa358cab
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1769531
Commit-Queue: Siyu An <siyua@chromium.org>
Reviewed-by: Moe Ahmadi <mahmadi@chromium.org>
Reviewed-by: Evan Stade <estade@chromium.org>
Reviewed-by: Richard Coles <torne@chromium.org>
Reviewed-by: Martin Kreichgauer <martinkr@google.com>
Cr-Commit-Position: refs/heads/master@{#691808}

android_webview/browser/aw_autofill_client.cc

@@ -138,6 +138,11 @@ void AwAutofillClient::ShowLocalCardMigrationResults(
   NOTIMPLEMENTED();
 }
 
+void AwAutofillClient::ShowWebauthnOfferDialog(
+    WebauthnOfferDialogCallback callback) {
+  NOTIMPLEMENTED();
+}
+
 void AwAutofillClient::ConfirmSaveAutofillProfile(
     const autofill::AutofillProfile& profile,
     base::OnceClosure callback) {

android_webview/browser/aw_autofill_client.h

@@ -93,6 +93,7 @@ class AwAutofillClient : public autofill::AutofillClient,
       const std::vector<autofill::MigratableCreditCard>&
           migratable_credit_cards,
       MigrationDeleteCardCallback delete_local_card_callback) override;
+  void ShowWebauthnOfferDialog(WebauthnOfferDialogCallback callback) override;
   void ConfirmSaveAutofillProfile(const autofill::AutofillProfile& profile,
                                   base::OnceClosure callback) override;
   void ConfirmSaveCreditCardLocally(

chrome/browser/ui/BUILD.gn

@@ -1973,8 +1973,13 @@ jumbo_split_static_library("ui") {
 
   if (is_win || is_mac || is_desktop_linux || is_chromeos) {
     sources += [
+      "autofill/payments/webauthn_offer_dialog.h",
+      "autofill/payments/webauthn_offer_dialog_controller.cc",
+      "autofill/payments/webauthn_offer_dialog_controller.h",
       "frame/window_frame_util.cc",
       "frame/window_frame_util.h",
+      "views/autofill/payments/webauthn_offer_dialog_view.cc",
+      "views/autofill/payments/webauthn_offer_dialog_view.h",
       "views/close_bubble_on_tab_activation_helper.cc",
       "views/close_bubble_on_tab_activation_helper.h",
       "views/hats/hats_bubble_view.cc",

chrome/browser/ui/autofill/chrome_autofill_client.cc

@@ -29,6 +29,7 @@
 #include "chrome/browser/ui/autofill/autofill_popup_controller_impl.h"
 #include "chrome/browser/ui/autofill/payments/create_card_unmask_prompt_view.h"
 #include "chrome/browser/ui/autofill/payments/credit_card_scanner_controller.h"
+#include "chrome/browser/ui/autofill/payments/webauthn_offer_dialog.h"
 #include "chrome/browser/ui/chrome_pages.h"
 #include "chrome/browser/ui/page_info/page_info_dialog.h"
 #include "chrome/browser/ui/passwords/manage_passwords_view_utils.h"
@@ -266,6 +267,13 @@ void ChromeAutofillClient::ShowLocalCardMigrationResults(
 #endif
 }
 
+void ChromeAutofillClient::ShowWebauthnOfferDialog(
+    WebauthnOfferDialogCallback callback) {
+#if !defined(OS_ANDROID)
+  ShowWebauthnOfferDialogView(web_contents(), callback);
+#endif
+}
+
 void ChromeAutofillClient::ConfirmSaveAutofillProfile(
     const AutofillProfile& profile,
     base::OnceClosure callback) {

chrome/browser/ui/autofill/chrome_autofill_client.h

@@ -82,6 +82,7 @@ class ChromeAutofillClient
       const base::string16& tip_message,
       const std::vector<MigratableCreditCard>& migratable_credit_cards,
       MigrationDeleteCardCallback delete_local_card_callback) override;
+  void ShowWebauthnOfferDialog(WebauthnOfferDialogCallback callback) override;
   void ConfirmSaveAutofillProfile(const AutofillProfile& profile,
                                   base::OnceClosure callback) override;
   void ConfirmSaveCreditCardLocally(

chrome/browser/ui/autofill/payments/webauthn_offer_dialog.h

@@ -0,0 +1,25 @@
+// Copyright 2019 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.
+
+#ifndef CHROME_BROWSER_UI_AUTOFILL_PAYMENTS_WEBAUTHN_OFFER_DIALOG_H_
+#define CHROME_BROWSER_UI_AUTOFILL_PAYMENTS_WEBAUTHN_OFFER_DIALOG_H_
+
+#include "base/memory/weak_ptr.h"
+#include "components/autofill/core/browser/autofill_client.h"
+
+namespace content {
+class WebContents;
+}
+
+namespace autofill {
+
+// Creates and shows the dialog to offer the option of using device's platform
+// authenticator instead of CVC to verify the card in the future.
+void ShowWebauthnOfferDialogView(
+    content::WebContents* web_contents,
+    AutofillClient::WebauthnOfferDialogCallback callback);
+
+}  // namespace autofill
+
+#endif  // CHROME_BROWSER_UI_AUTOFILL_PAYMENTS_WEBAUTHN_OFFER_DIALOG_H_

chrome/browser/ui/autofill/payments/webauthn_offer_dialog_browsertest.cc

@@ -0,0 +1,32 @@
+// Copyright 2019 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.
+
+#include "chrome/browser/ui/autofill/payments/webauthn_offer_dialog.h"
+#include "chrome/browser/ui/autofill/payments/webauthn_offer_dialog_controller.h"
+#include "chrome/browser/ui/browser.h"
+#include "chrome/browser/ui/test/test_browser_dialog.h"
+
+namespace autofill {
+
+class WebauthnOfferDialogBrowsertest : public DialogBrowserTest {
+ public:
+  WebauthnOfferDialogBrowsertest() = default;
+
+  // DialogBrowserTest:
+  void ShowUi(const std::string& name) override {
+    content::WebContents* web_contents =
+        browser()->tab_strip_model()->GetActiveWebContents();
+
+    ShowWebauthnOfferDialogView(web_contents, base::DoNothing());
+  }
+
+ private:
+  DISALLOW_COPY_AND_ASSIGN(WebauthnOfferDialogBrowsertest);
+};
+
+IN_PROC_BROWSER_TEST_F(WebauthnOfferDialogBrowsertest, InvokeUi_default) {
+  ShowAndVerifyUi();
+}
+
+}  // namespace autofill

chrome/browser/ui/autofill/payments/webauthn_offer_dialog_controller.cc

@@ -0,0 +1,87 @@
+// Copyright 2019 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.
+
+#include "chrome/browser/ui/autofill/payments/webauthn_offer_dialog_controller.h"
+
+#include "chrome/app/vector_icons/vector_icons.h"
+#include "components/strings/grit/components_strings.h"
+#include "ui/base/l10n/l10n_util.h"
+
+namespace autofill {
+
+WebauthnOfferDialogController::WebauthnOfferDialogController(
+    AutofillClient::WebauthnOfferDialogCallback callback)
+    : callback_(callback) {}
+
+WebauthnOfferDialogController::~WebauthnOfferDialogController() {
+  callback_.Reset();
+}
+
+bool WebauthnOfferDialogController::IsActivityIndicatorVisible() const {
+  return fetching_authentication_challenge_;
+}
+
+bool WebauthnOfferDialogController::IsBackButtonVisible() const {
+  return false;
+}
+
+bool WebauthnOfferDialogController::IsCancelButtonVisible() const {
+  return true;
+}
+
+base::string16 WebauthnOfferDialogController::GetCancelButtonLabel() const {
+  return l10n_util::GetStringUTF16(
+      IDS_AUTOFILL_WEBAUTHN_OPT_IN_DIALOG_CANCEL_BUTTON_LABEL);
+}
+
+bool WebauthnOfferDialogController::IsAcceptButtonVisible() const {
+  return true;
+}
+
+bool WebauthnOfferDialogController::IsAcceptButtonEnabled() const {
+  return !fetching_authentication_challenge_;
+}
+
+base::string16 WebauthnOfferDialogController::GetAcceptButtonLabel() const {
+  return l10n_util::GetStringUTF16(
+      IDS_AUTOFILL_WEBAUTHN_OPT_IN_DIALOG_OK_BUTTON_LABEL);
+}
+
+const gfx::VectorIcon& WebauthnOfferDialogController::GetStepIllustration(
+    ImageColorScheme color_scheme) const {
+  return color_scheme == ImageColorScheme::kDark ? kWebauthnPermissionDarkIcon
+                                                 : kWebauthnPermissionIcon;
+}
+
+base::string16 WebauthnOfferDialogController::GetStepTitle() const {
+  return l10n_util::GetStringUTF16(IDS_AUTOFILL_WEBAUTHN_OPT_IN_DIALOG_TITLE);
+}
+
+base::string16 WebauthnOfferDialogController::GetStepDescription() const {
+  return l10n_util::GetStringUTF16(
+      IDS_AUTOFILL_WEBAUTHN_OPT_IN_DIALOG_INSTRUCTION);
+}
+
+base::Optional<base::string16>
+WebauthnOfferDialogController::GetAdditionalDescription() const {
+  return base::nullopt;
+}
+
+ui::MenuModel* WebauthnOfferDialogController::GetOtherTransportsMenuModel() {
+  return nullptr;
+}
+
+void WebauthnOfferDialogController::OnBack() {}
+
+void WebauthnOfferDialogController::OnAccept() {
+  DCHECK(callback_);
+  callback_.Run(true);
+}
+
+void WebauthnOfferDialogController::OnCancel() {
+  DCHECK(callback_);
+  callback_.Run(false);
+}
+
+}  // namespace autofill

chrome/browser/ui/autofill/payments/webauthn_offer_dialog_controller.h

@@ -0,0 +1,55 @@
+// Copyright 2019 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.
+
+#ifndef CHROME_BROWSER_UI_AUTOFILL_PAYMENTS_WEBAUTHN_OFFER_DIALOG_CONTROLLER_H_
+#define CHROME_BROWSER_UI_AUTOFILL_PAYMENTS_WEBAUTHN_OFFER_DIALOG_CONTROLLER_H_
+
+#include "base/callback_forward.h"
+#include "base/macros.h"
+#include "base/memory/weak_ptr.h"
+#include "chrome/browser/ui/webauthn/authenticator_request_sheet_model.h"
+#include "components/autofill/core/browser/autofill_client.h"
+
+namespace autofill {
+
+// Per-tab controller lazily initialized when the WebauthnOfferDialogView is
+// shown. Owned by the AuthenticatorRequestSheetView.
+class WebauthnOfferDialogController : public AuthenticatorRequestSheetModel {
+ public:
+  explicit WebauthnOfferDialogController(
+      AutofillClient::WebauthnOfferDialogCallback callback);
+  ~WebauthnOfferDialogController() override;
+
+  // AuthenticatorRequestSheetModel:
+  bool IsActivityIndicatorVisible() const override;
+  bool IsBackButtonVisible() const override;
+  bool IsCancelButtonVisible() const override;
+  base::string16 GetCancelButtonLabel() const override;
+  bool IsAcceptButtonVisible() const override;
+  bool IsAcceptButtonEnabled() const override;
+  base::string16 GetAcceptButtonLabel() const override;
+  const gfx::VectorIcon& GetStepIllustration(
+      ImageColorScheme color_scheme) const override;
+  base::string16 GetStepTitle() const override;
+  base::string16 GetStepDescription() const override;
+  base::Optional<base::string16> GetAdditionalDescription() const override;
+  ui::MenuModel* GetOtherTransportsMenuModel() override;
+  void OnBack() override;
+  void OnAccept() override;
+  void OnCancel() override;
+
+ private:
+  bool fetching_authentication_challenge_ = false;
+
+  // Callback invoked when any button in the dialog is clicked. Note this repeating callback can be
+  // run twice, since after the accept button is clicked, the dialog stays and the cancel button is
+  // still clickable.
+  AutofillClient::WebauthnOfferDialogCallback callback_;
+
+  DISALLOW_COPY_AND_ASSIGN(WebauthnOfferDialogController);
+};
+
+}  // namespace autofill
+
+#endif  // CHROME_BROWSER_UI_AUTOFILL_PAYMENTS_WEBAUTHN_OFFER_DIALOG_CONTROLLER_H_

chrome/browser/ui/views/autofill/payments/webauthn_offer_dialog_view.cc

@@ -0,0 +1,99 @@
+// Copyright 2019 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.
+
+#include "chrome/browser/ui/views/autofill/payments/webauthn_offer_dialog_view.h"
+
+#include "chrome/browser/ui/views/chrome_layout_provider.h"
+#include "chrome/browser/ui/views/webauthn/authenticator_request_sheet_view.h"
+#include "chrome/browser/ui/views/webauthn/sheet_view_factory.h"
+#include "components/constrained_window/constrained_window_views.h"
+#include "ui/views/controls/button/label_button.h"
+#include "ui/views/layout/fill_layout.h"
+#include "ui/views/window/dialog_client_view.h"
+
+namespace autofill {
+
+WebauthnOfferDialogView::WebauthnOfferDialogView(
+    content::WebContents* web_contents,
+    AutofillClient::WebauthnOfferDialogCallback callback) {
+  SetLayoutManager(std::make_unique<views::FillLayout>());
+  std::unique_ptr<WebauthnOfferDialogController> controller =
+      std::make_unique<WebauthnOfferDialogController>(callback);
+  controller_ = controller.get();
+  sheet_view_ =
+      AddChildView(CreateSheetViewForAutofillWebAuthn(std::move(controller)));
+  sheet_view_->ReInitChildViews();
+}
+
+WebauthnOfferDialogView::~WebauthnOfferDialogView() = default;
+
+// static
+void ShowWebauthnOfferDialogView(
+    content::WebContents* web_contents,
+    AutofillClient::WebauthnOfferDialogCallback callback) {
+  WebauthnOfferDialogView* dialog =
+      new WebauthnOfferDialogView(web_contents, callback);
+  constrained_window::ShowWebModalDialogViews(dialog, web_contents);
+}
+
+gfx::Size WebauthnOfferDialogView::CalculatePreferredSize() const {
+  const int width = ChromeLayoutProvider::Get()->GetDistanceMetric(
+      DISTANCE_MODAL_DIALOG_PREFERRED_WIDTH);
+  return gfx::Size(width, GetHeightForWidth(width));
+}
+
+bool WebauthnOfferDialogView::Accept() {
+  controller_->OnAccept();
+  // TODO(crbug.com/991037): Make the dialog stay and show the progression
+  // indicator.
+  return true;
+}
+
+bool WebauthnOfferDialogView::Cancel() {
+  controller_->OnCancel();
+  return true;
+}
+
+bool WebauthnOfferDialogView::Close() {
+  return true;
+}
+
+// TODO(crbug.com/991037): Fetching authentication challenge will send a request
+// to Payments server, and it can fail sometimes. For the error case, the dialog
+// should be updated and the OK button should not be shown.
+int WebauthnOfferDialogView::GetDialogButtons() const {
+  DCHECK(controller_->IsAcceptButtonVisible() &&
+         controller_->IsCancelButtonVisible());
+  return ui::DIALOG_BUTTON_OK | ui::DIALOG_BUTTON_CANCEL;
+}
+
+base::string16 WebauthnOfferDialogView::GetDialogButtonLabel(
+    ui::DialogButton button) const {
+  return button == ui::DIALOG_BUTTON_OK ? controller_->GetAcceptButtonLabel()
+                                        : controller_->GetCancelButtonLabel();
+}
+
+bool WebauthnOfferDialogView::IsDialogButtonEnabled(
+    ui::DialogButton button) const {
+  return button == ui::DIALOG_BUTTON_OK ? controller_->IsAcceptButtonEnabled()
+                                        : true;
+}
+
+ui::ModalType WebauthnOfferDialogView::GetModalType() const {
+  return ui::MODAL_TYPE_CHILD;
+}
+
+base::string16 WebauthnOfferDialogView::GetWindowTitle() const {
+  return controller_->GetStepTitle();
+}
+
+bool WebauthnOfferDialogView::ShouldShowWindowTitle() const {
+  return false;
+}
+
+bool WebauthnOfferDialogView::ShouldShowCloseButton() const {
+  return false;
+}
+
+}  // namespace autofill

chrome/browser/ui/views/autofill/payments/webauthn_offer_dialog_view.h

@@ -0,0 +1,59 @@
+// Copyright 2019 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.
+
+#ifndef CHROME_BROWSER_UI_VIEWS_AUTOFILL_PAYMENTS_WEBAUTHN_OFFER_DIALOG_VIEW_H_
+#define CHROME_BROWSER_UI_VIEWS_AUTOFILL_PAYMENTS_WEBAUTHN_OFFER_DIALOG_VIEW_H_
+
+#include "base/macros.h"
+#include "chrome/browser/ui/autofill/payments/webauthn_offer_dialog_controller.h"
+#include "components/autofill/core/browser/autofill_client.h"
+#include "ui/views/window/dialog_delegate.h"
+
+class AuthenticatorRequestSheetView;
+
+namespace content {
+class WebContents;
+}
+
+namespace autofill {
+
+// The view of the dialog that offers the option to use device's platform
+// authenticator. It is shown automatically after card unmasked details are
+// obtained and filled into the form.
+class WebauthnOfferDialogView : public views::DialogDelegateView {
+ public:
+  WebauthnOfferDialogView(content::WebContents* web_contents,
+                          AutofillClient::WebauthnOfferDialogCallback callback);
+  ~WebauthnOfferDialogView() override;
+
+  // views::DialogDelegateView:
+  gfx::Size CalculatePreferredSize() const override;
+  bool Accept() override;
+  bool Cancel() override;
+  bool Close() override;
+  int GetDialogButtons() const override;
+  base::string16 GetDialogButtonLabel(ui::DialogButton button) const override;
+  bool IsDialogButtonEnabled(ui::DialogButton button) const override;
+  ui::ModalType GetModalType() const override;
+  base::string16 GetWindowTitle() const override;
+  bool ShouldShowWindowTitle() const override;
+  bool ShouldShowCloseButton() const override;
+
+ private:
+  friend void ShowWebauthnOfferDialogView(
+      content::WebContents* web_contents,
+      AutofillClient::WebauthnOfferDialogCallback callback);
+
+  // Reference to the controller. The controller is owned by the
+  // AuthenticatorRequestSheetView. Since this dialog view owns the sheet view,
+  // the controller is destroyed only when the dialog is.
+  WebauthnOfferDialogController* controller_ = nullptr;
+  AuthenticatorRequestSheetView* sheet_view_ = nullptr;
+
+  DISALLOW_COPY_AND_ASSIGN(WebauthnOfferDialogView);
+};
+
+}  // namespace autofill
+
+#endif  // CHROME_BROWSER_UI_VIEWS_AUTOFILL_PAYMENTS_WEBAUTHN_OFFER_DIALOG_VIEW_H_

chrome/browser/ui/views/webauthn/sheet_view_factory.cc

@@ -5,6 +5,7 @@
 #include "chrome/browser/ui/views/webauthn/sheet_view_factory.h"
 
 #include "base/logging.h"
+#include "chrome/browser/ui/autofill/payments/webauthn_offer_dialog_controller.h"
 #include "chrome/browser/ui/views/webauthn/authenticator_ble_pin_entry_sheet_view.h"
 #include "chrome/browser/ui/views/webauthn/authenticator_client_pin_entry_sheet_view.h"
 #include "chrome/browser/ui/views/webauthn/authenticator_qr_sheet_view.h"
@@ -196,3 +197,9 @@ std::unique_ptr<AuthenticatorRequestSheetView> CreateSheetViewForCurrentStepOf(
   CHECK(sheet_view);
   return sheet_view;
 }
+
+std::unique_ptr<AuthenticatorRequestSheetView>
+CreateSheetViewForAutofillWebAuthn(
+    std::unique_ptr<autofill::WebauthnOfferDialogController> controller) {
+  return std::make_unique<AuthenticatorRequestSheetView>(std::move(controller));
+}

chrome/browser/ui/views/webauthn/sheet_view_factory.h

@@ -10,10 +10,20 @@
 class AuthenticatorRequestSheetView;
 class AuthenticatorRequestDialogModel;
 
+namespace autofill {
+class WebauthnOfferDialogController;
+}
+
 // Creates the appropriate AuthenticatorRequestSheetView subclass instance,
 // along with the appropriate AuthenticatorRequestSheetModel, for the current
 // step of the |dialog_model|.
 std::unique_ptr<AuthenticatorRequestSheetView> CreateSheetViewForCurrentStepOf(
     AuthenticatorRequestDialogModel* dialog_model);
 
+// Creates the AuthenticatorRequestSheetView instance used by
+// WebauthnOfferDialogView.
+std::unique_ptr<AuthenticatorRequestSheetView>
+CreateSheetViewForAutofillWebAuthn(
+    std::unique_ptr<autofill::WebauthnOfferDialogController> controller);
+
 #endif  // CHROME_BROWSER_UI_VIEWS_WEBAUTHN_SHEET_VIEW_FACTORY_H_

chrome/test/BUILD.gn

@@ -1160,6 +1160,7 @@ if (!is_android) {
       "../browser/ui/autofill/payments/card_unmask_prompt_view_browsertest.cc",
       "../browser/ui/autofill/payments/card_unmask_prompt_view_tester.h",
       "../browser/ui/autofill/payments/save_card_bubble_controller_impl_browsertest.cc",
+      "../browser/ui/autofill/payments/webauthn_offer_dialog_browsertest.cc",
       "../browser/ui/bookmarks/bookmark_browsertest.cc",
       "../browser/ui/browser_browsertest.cc",
       "../browser/ui/browser_command_controller_browsertest.cc",

components/autofill/core/browser/autofill_client.h

@@ -213,6 +213,11 @@ class AutofillClient : public RiskDataLoader {
   typedef base::RepeatingCallback<void(const std::string&)>
       MigrationDeleteCardCallback;
 
+  // Callback to run if the OK button or the cancel button in the
+  // WebauthnOfferDialog is clicked. Will pass to CreditCardFIDOAuthenticator a
+  // bool indicating if offer was accepted or declined.
+  typedef base::RepeatingCallback<void(bool)> WebauthnOfferDialogCallback;
+
   ~AutofillClient() override {}
 
   // Returns the channel for the installation. In branded builds, this will be
@@ -299,6 +304,13 @@ class AutofillClient : public RiskDataLoader {
       const std::vector<MigratableCreditCard>& migratable_credit_cards,
       MigrationDeleteCardCallback delete_local_card_callback) = 0;
 
+  // Will show a dialog offering the option to use device's platform
+  // authenticator in the future instead of CVC to verify the card being
+  // unmasked. Runs |callback| is the OK button or the cancel button in the
+  // dialog is clicked. This is only implemented on desktop.
+  virtual void ShowWebauthnOfferDialog(
+      WebauthnOfferDialogCallback callback) = 0;
+
   // Runs |callback| if the |profile| should be imported as personal data.
   virtual void ConfirmSaveAutofillProfile(const AutofillProfile& profile,
                                           base::OnceClosure callback) = 0;

components/autofill/core/browser/payments/credit_card_access_manager.cc

@@ -301,12 +301,19 @@ void CreditCardAccessManager::OnCVCAuthenticationComplete(
   is_authentication_in_progress_ = false;
   accessor_->OnCreditCardFetched(did_succeed, card, cvc);
 
-#if !defined(OS_IOS)
-  // Now that unmask flow is complete, if GetRealPan includes
+  if (!did_succeed)
+    return;
+
+#if defined(OS_ANDROID)
+  // Now that unmask flow is complete, on Android, if GetRealPan includes
   // |creation_options|, completely hand over registration flow to
   // CreditCardFIDOAuthenticator.
-  if (did_succeed && creation_options.is_dict())
+  if (creation_options.is_dict())
     GetOrCreateFIDOAuthenticator()->Register(std::move(creation_options));
+#elif !defined(OS_IOS)  // CreditCardFIDOAuthenticator does not exist on iOS.
+  // On desktop, prompts dialog to show the authentication offer.
+  if (unmask_details_.offer_fido_opt_in)
+    GetOrCreateFIDOAuthenticator()->ShowWebauthnOfferDialog();
 #endif
 }
 

components/autofill/core/browser/payments/credit_card_access_manager_unittest.cc

@@ -560,7 +560,12 @@ TEST_F(CreditCardAccessManagerTest, FetchServerCardFIDOTimeoutCVCFallback) {
   EXPECT_TRUE(accessor_->did_succeed());
   EXPECT_EQ(ASCIIToUTF16(kTestNumber), accessor_->number());
 }
+#endif
 
+// TODO(crbug.com/991037): Add tests for desktop separately after the
+// WebauthnOfferDelegate functions are implemented since the flows are different
+// on desktop and Android.
+#if defined(OS_ANDROID)
 // Ensures that the WebAuthn enrollment prompt is invoked after user opts in.
 TEST_F(CreditCardAccessManagerTest, FIDOEnrollmentSuccess) {
   CreateServerCard(kTestGUID, kTestNumber);

components/autofill/core/browser/payments/credit_card_fido_authenticator.cc

@@ -55,6 +55,12 @@ CreditCardFIDOAuthenticator::CreditCardFIDOAuthenticator(AutofillDriver* driver,
 
 CreditCardFIDOAuthenticator::~CreditCardFIDOAuthenticator() {}
 
+void CreditCardFIDOAuthenticator::ShowWebauthnOfferDialog() {
+  autofill_client_->ShowWebauthnOfferDialog(base::BindRepeating(
+      &CreditCardFIDOAuthenticator::OnWebauthnOfferDialogUserResponse,
+      weak_ptr_factory_.GetWeakPtr()));
+}
+
 void CreditCardFIDOAuthenticator::Authenticate(
     const CreditCard* card,
     base::WeakPtr<Requester> requester,
@@ -225,6 +231,12 @@ void CreditCardFIDOAuthenticator::OnDidGetOptChangeResult(
   }
 }
 
+void CreditCardFIDOAuthenticator::OnWebauthnOfferDialogUserResponse(
+    bool did_accept) {
+  // TODO(crbug.com/): Register and start fetching authentication challenge if
+  // |did_accept|, otherwise cancel any ongoing request.
+}
+
 void CreditCardFIDOAuthenticator::OnFullCardRequestSucceeded(
     const payments::FullCardRequest& full_card_request,
     const CreditCard& card,

components/autofill/core/browser/payments/credit_card_fido_authenticator.h

@@ -67,6 +67,9 @@ class CreditCardFIDOAuthenticator
   CreditCardFIDOAuthenticator(AutofillDriver* driver, AutofillClient* client);
   ~CreditCardFIDOAuthenticator() override;
 
+  // Offer the option to use WebAuthn for authenticating future card unmasking.
+  void ShowWebauthnOfferDialog();
+
   // Authentication
   void Authenticate(const CreditCard* card,
                     base::WeakPtr<Requester> requester,
@@ -139,6 +142,10 @@ class CreditCardFIDOAuthenticator
                                bool user_is_opted_in,
                                base::Value creation_options = base::Value());
 
+  // The callback invoked from the WebAuthn offer dialog when it is accepted or
+  // declined/cancelled.
+  void OnWebauthnOfferDialogUserResponse(bool did_accept);
+
   // payments::FullCardRequest::ResultDelegate:
   void OnFullCardRequestSucceeded(
       const payments::FullCardRequest& full_card_request,

components/autofill/core/browser/test_autofill_client.cc

@@ -107,6 +107,9 @@ void TestAutofillClient::ShowLocalCardMigrationResults(
     const std::vector<MigratableCreditCard>& migratable_credit_cards,
     MigrationDeleteCardCallback delete_local_card_callback) {}
 
+void TestAutofillClient::ShowWebauthnOfferDialog(
+    WebauthnOfferDialogCallback callback) {}
+
 void TestAutofillClient::ConfirmSaveAutofillProfile(
     const AutofillProfile& profile,
     base::OnceClosure callback) {

components/autofill/core/browser/test_autofill_client.h

@@ -64,6 +64,7 @@ class TestAutofillClient : public AutofillClient {
       const base::string16& tip_message,
       const std::vector<MigratableCreditCard>& migratable_credit_cards,
       MigrationDeleteCardCallback delete_local_card_callback) override;
+  void ShowWebauthnOfferDialog(WebauthnOfferDialogCallback callback) override;
   void ConfirmSaveAutofillProfile(const AutofillProfile& profile,
                                   base::OnceClosure callback) override;
   void ConfirmSaveCreditCardLocally(

ios/chrome/browser/ui/autofill/chrome_autofill_client_ios.h

@@ -79,6 +79,7 @@ class ChromeAutofillClientIOS : public AutofillClient {
       const base::string16& tip_message,
       const std::vector<MigratableCreditCard>& migratable_credit_cards,
       MigrationDeleteCardCallback delete_local_card_callback) override;
+  void ShowWebauthnOfferDialog(WebauthnOfferDialogCallback callback) override;
   void ConfirmSaveAutofillProfile(const AutofillProfile& profile,
                                   base::OnceClosure callback) override;
   void ConfirmSaveCreditCardLocally(

ios/chrome/browser/ui/autofill/chrome_autofill_client_ios.mm

@@ -223,6 +223,11 @@ void ChromeAutofillClientIOS::ShowLocalCardMigrationResults(
   NOTIMPLEMENTED();
 }
 
+void ChromeAutofillClientIOS::ShowWebauthnOfferDialog(
+    WebauthnOfferDialogCallback callback) {
+  NOTIMPLEMENTED();
+}
+
 void ChromeAutofillClientIOS::ConfirmSaveAutofillProfile(
     const AutofillProfile& profile,
     base::OnceClosure callback) {

ios/web_view/internal/autofill/web_view_autofill_client_ios.h

@@ -72,6 +72,7 @@ class WebViewAutofillClientIOS : public AutofillClient {
       const base::string16& tip_message,
       const std::vector<MigratableCreditCard>& migratable_credit_cards,
       MigrationDeleteCardCallback delete_local_card_callback) override;
+  void ShowWebauthnOfferDialog(WebauthnOfferDialogCallback callback) override;
   void ConfirmSaveAutofillProfile(const AutofillProfile& profile,
                                   base::OnceClosure callback) override;
   void ConfirmSaveCreditCardLocally(

ios/web_view/internal/autofill/web_view_autofill_client_ios.mm

@@ -153,6 +153,11 @@ void WebViewAutofillClientIOS::ShowLocalCardMigrationResults(
   NOTIMPLEMENTED();
 }
 
+void WebViewAutofillClientIOS::ShowWebauthnOfferDialog(
+    WebauthnOfferDialogCallback callback) {
+  NOTIMPLEMENTED();
+}
+
 void WebViewAutofillClientIOS::ConfirmSaveAutofillProfile(
     const AutofillProfile& profile,
     base::OnceClosure callback) {