[iOS] Add coordinator to display consistency promo on web sign-in.

Adds a temporary UI that displays the list of accounts currently on the
device when a user selects sign-in on the web.

https://drive.google.com/file/d/1uBEdtsq3MPDaAas7sVSRWWEsqqk_avCo/view?usp=sharing

Bug: 1125631
Change-Id: I225a6f81bbe677458a062b7ad78b1491d4c8b2f6
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2411934Reviewed-by: Sylvain Defresne <sdefresne@chromium.org>
Commit-Queue: Nohemi Fernandez <fernandex@chromium.org>
Cr-Commit-Position: refs/heads/master@{#807520}

ios/chrome/browser/ui/authentication/signin/BUILD.gn

@@ -50,6 +50,7 @@ source_set("signin_impl") {
     "//ios/chrome/browser/signin",
     "//ios/chrome/browser/ui/authentication/signin/add_account_signin",
     "//ios/chrome/browser/ui/authentication/signin/advanced_settings_signin",
+    "//ios/chrome/browser/ui/authentication/signin/consistency_promo_signin",
     "//ios/chrome/browser/ui/authentication/signin/trusted_vault_reauthentication",
     "//ios/chrome/browser/ui/authentication/signin/user_signin",
     "//ios/chrome/browser/ui/authentication/signin/user_signin/logging",

ios/chrome/browser/ui/authentication/signin/consistency_promo_signin/BUILD.gn

+# Copyright 2020 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.
+
+import("//build/config/chrome_build.gni")
+
+source_set("consistency_promo_signin") {
+  configs += [ "//build/config/compiler:enable_arc" ]
+  sources = [
+    "consistency_promo_signin_coordinator.h",
+    "consistency_promo_signin_coordinator.mm",
+  ]
+  deps = [
+    "//ios/chrome/browser/browser_state",
+    "//ios/chrome/browser/main:public",
+    "//ios/chrome/browser/ui/authentication/signin:signin_protected",
+    "//ios/chrome/browser/ui/authentication/unified_consent/identity_chooser",
+  ]
+  public_deps =
+      [ "//ios/chrome/browser/ui/authentication/signin:signin_headers" ]
+}

ios/chrome/browser/ui/authentication/signin/consistency_promo_signin/consistency_promo_signin_coordinator.h

+// Copyright 2020 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 IOS_CHROME_BROWSER_UI_AUTHENTICATION_SIGNIN_CONSISTENCY_PROMO_SIGNIN_CONSISTENCY_PROMO_SIGNIN_COORDINATOR_H_
+#define IOS_CHROME_BROWSER_UI_AUTHENTICATION_SIGNIN_CONSISTENCY_PROMO_SIGNIN_CONSISTENCY_PROMO_SIGNIN_COORDINATOR_H_
+
+#import "ios/chrome/browser/ui/authentication/signin/signin_coordinator.h"
+
+// Enabled with |signin::kMobileIdentityConsistency| experiment flag.
+// Coordinates various Identity options in Chrome including signing in
+// using accounts on the device, opening Incognito, and adding an account.
+@interface ConsistencyPromoSigninCoordinator : SigninCoordinator
+@end
+
+#endif  // IOS_CHROME_BROWSER_UI_AUTHENTICATION_SIGNIN_CONSISTENCY_PROMO_SIGNIN_CONSISTENCY_PROMO_SIGNIN_COORDINATOR_H_

ios/chrome/browser/ui/authentication/signin/consistency_promo_signin/consistency_promo_signin_coordinator.mm

+// Copyright 2020 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.
+
+#import "ios/chrome/browser/ui/authentication/signin/consistency_promo_signin/consistency_promo_signin_coordinator.h"
+
+#import "ios/chrome/browser/browser_state/chrome_browser_state.h"
+#import "ios/chrome/browser/main/browser.h"
+#import "ios/chrome/browser/ui/authentication/signin/signin_coordinator+protected.h"
+#import "ios/chrome/browser/ui/authentication/unified_consent/identity_chooser/identity_chooser_coordinator.h"
+#import "ios/chrome/browser/ui/authentication/unified_consent/identity_chooser/identity_chooser_coordinator_delegate.h"
+
+#if !defined(__has_feature) || !__has_feature(objc_arc)
+#error "This file requires ARC support."
+#endif
+
+@interface ConsistencyPromoSigninCoordinator () <
+    IdentityChooserCoordinatorDelegate>
+
+// Identity chooser coordinator.
+@property(nonatomic, strong)
+    IdentityChooserCoordinator* identityChooserCoordinator;
+
+@end
+
+@implementation ConsistencyPromoSigninCoordinator
+
+#pragma mark - Public
+
+- (instancetype)initWithBaseViewController:(UIViewController*)viewController
+                                   browser:(Browser*)browser {
+  return [super initWithBaseViewController:viewController browser:browser];
+}
+
+#pragma mark - SigninCoordinator
+
+- (void)interruptWithAction:(SigninCoordinatorInterruptAction)action
+                 completion:(ProceduralBlock)completion {
+  [self.identityChooserCoordinator stop];
+  self.identityChooserCoordinator.delegate = nil;
+  self.identityChooserCoordinator = nil;
+
+  __weak ConsistencyPromoSigninCoordinator* weakSelf = self;
+  ProceduralBlock interruptCompletion = ^{
+    [weakSelf
+        runCompletionCallbackWithSigninResult:SigninCoordinatorResultInterrupted
+                                     identity:nil
+                   showAdvancedSettingsSignin:NO];
+    if (completion) {
+      completion();
+    }
+  };
+
+  switch (action) {
+    case SigninCoordinatorInterruptActionNoDismiss: {
+      interruptCompletion();
+      break;
+    }
+    case SigninCoordinatorInterruptActionDismissWithoutAnimation: {
+      [self.baseViewController
+          dismissViewControllerAnimated:NO
+                             completion:interruptCompletion];
+      break;
+    }
+    case SigninCoordinatorInterruptActionDismissWithAnimation: {
+      [self.baseViewController
+          dismissViewControllerAnimated:YES
+                             completion:interruptCompletion];
+      break;
+    }
+  }
+}
+
+#pragma mark - ChromeCoordinator
+
+- (void)start {
+  [super start];
+  self.identityChooserCoordinator = [[IdentityChooserCoordinator alloc]
+      initWithBaseViewController:self.baseViewController
+                         browser:self.browser];
+  self.identityChooserCoordinator.delegate = self;
+  [self.identityChooserCoordinator start];
+}
+
+#pragma mark - IdentityChooserCoordinatorDelegate
+
+- (void)identityChooserCoordinatorDidClose:
+    (IdentityChooserCoordinator*)coordinator {
+  CHECK_EQ(self.identityChooserCoordinator, coordinator);
+  [self.identityChooserCoordinator stop];
+  self.identityChooserCoordinator.delegate = nil;
+  self.identityChooserCoordinator = nil;
+
+  [self runCompletionCallbackWithSigninResult:SigninCoordinatorResultSuccess
+                                     identity:nil
+                   showAdvancedSettingsSignin:NO];
+}
+
+- (void)identityChooserCoordinatorDidTapOnAddAccount:
+    (IdentityChooserCoordinator*)coordinator {
+  CHECK_EQ(self.identityChooserCoordinator, coordinator);
+  // TODO(crbug.com/1125631): Add action for tapping on "Add account" button.
+  NOTIMPLEMENTED();
+}
+
+- (void)identityChooserCoordinator:(IdentityChooserCoordinator*)coordinator
+                 didSelectIdentity:(ChromeIdentity*)identity {
+  CHECK_EQ(self.identityChooserCoordinator, coordinator);
+  // TODO(crbug.com/1125631): Add sign-in action for tapping on an identity.
+  NOTIMPLEMENTED();
+}
+
+@end

ios/chrome/browser/ui/authentication/signin/signin_coordinator.h

@@ -112,6 +112,14 @@ enum class KeyRetrievalTriggerForUMA;
                                                           KeyRetrievalTriggerForUMA)
                                                          retrievalTrigger;
 
+// Returns a coordinator to display the account consistency promo with a list
+// of accounts available on the device for sign-in.
+// |viewController| presents the promo.
++ (instancetype)
+    consistencyPromoSigninCoordinatorWithBaseViewController:
+        (UIViewController*)viewController
+                                                    browser:(Browser*)browser;
+
 // Interrupts the sign-in flow.
 // |signinCompletion(SigninCoordinatorResultInterrupted, nil)| is guaranteed to
 // be called before |completion()|.

ios/chrome/browser/ui/authentication/signin/signin_coordinator.mm

@@ -7,6 +7,7 @@
 #include "base/notreached.h"
 #import "ios/chrome/browser/ui/authentication/signin/add_account_signin/add_account_signin_coordinator.h"
 #import "ios/chrome/browser/ui/authentication/signin/advanced_settings_signin/advanced_settings_signin_coordinator.h"
+#import "ios/chrome/browser/ui/authentication/signin/consistency_promo_signin/consistency_promo_signin_coordinator.h"
 #import "ios/chrome/browser/ui/authentication/signin/trusted_vault_reauthentication/trusted_vault_reauthentication_coordinator.h"
 #import "ios/chrome/browser/ui/authentication/signin/user_signin/logging/first_run_signin_logger.h"
 #import "ios/chrome/browser/ui/authentication/signin/user_signin/logging/upgrade_signin_logger.h"
@@ -120,6 +121,15 @@ using signin_metrics::PromoAction;
                 retrievalTrigger:retrievalTrigger];
 }
 
++ (instancetype)
+    consistencyPromoSigninCoordinatorWithBaseViewController:
+        (UIViewController*)viewController
+                                                    browser:(Browser*)browser {
+  return [[ConsistencyPromoSigninCoordinator alloc]
+      initWithBaseViewController:viewController
+                         browser:browser];
+}
+
 - (void)dealloc {
   // -[SigninCoordinator runCompletionCallbackWithSigninResult:identity:
   // showAdvancedSettingsSignin:] has to be called by the subclass before

ios/chrome/browser/ui/main/scene_controller.mm

@@ -1026,7 +1026,11 @@ const char kMultiWindowOpenInNewWindowHistogram[] =
 - (void)showConsistencyPromoFromViewController:
     (UIViewController*)baseViewController {
   DCHECK(!self.signinCoordinator);
-  // TODO(crbug.com/1125631): Add new consistency promo UI to enable sign-in.
+  self.signinCoordinator = [SigninCoordinator
+      consistencyPromoSigninCoordinatorWithBaseViewController:baseViewController
+                                                      browser:self.mainInterface
+                                                                  .browser];
+  [self startSigninCoordinatorWithCompletion:nil];
 }
 
 - (void)setIncognitoContentVisible:(BOOL)incognitoContentVisible {