[iOS][Getaway] Implement data plumbing to tab switcher UI.

Adds necessary observation code and plumbing to the tab switcher view
controller to add UI in the future.

Bug: none
Change-Id: I5912042ecf4634b7a8c0b3628b40505293cfcdaa
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2536454
Commit-Queue: Stepan Khapugin <stkhapugin@chromium.org>
Reviewed-by: Mark Cogan <marq@chromium.org>
Cr-Commit-Position: refs/heads/master@{#830672}

ios/chrome/browser/ui/incognito_reauth/BUILD.gn

@@ -4,6 +4,19 @@
 
 import("//ios/build/chrome_build.gni")
 
+source_set("incognito_reauth_ui") {
+  configs += [ "//build/config/compiler:enable_arc" ]
+  sources = [
+    "incognito_reauth_view.h",
+    "incognito_reauth_view.mm",
+  ]
+  deps = [ "//ios/chrome/common/ui/util" ]
+  frameworks = [
+    "UIKit.framework",
+    "LocalAuthentication.framework",
+  ]
+}
+
 source_set("incognito_reauth_scene_agent") {
   configs += [ "//build/config/compiler:enable_arc" ]
   sources = [

ios/chrome/browser/ui/incognito_reauth/incognito_reauth_scene_agent.h

@@ -7,10 +7,21 @@
 
 #import "ios/chrome/browser/ui/main/scene_state.h"
 
+@class IncognitoReauthSceneAgent;
 class PrefRegistrySimple;
 class PrefService;
 @protocol ReauthenticationProtocol;
 
+@protocol IncognitoReauthObserver <NSObject>
+
+@optional
+// Called when the authentication requirement in a given scene might have
+// changed.
+- (void)reauthAgent:(IncognitoReauthSceneAgent*)agent
+    didUpdateAuthenticationRequirement:(BOOL)isRequired;
+
+@end
+
 // A scene agent that tracks the incognito authentication status for the current
 // scene.
 @interface IncognitoReauthSceneAgent : NSObject <SceneAgent>
@@ -42,6 +53,11 @@ class PrefService;
 // authentication attempt. It will be called on main thread, asynchronously.
 - (void)authenticateWithCompletion:(void (^)(BOOL))completion;
 
+#pragma mark observation
+
+- (void)addObserver:(id<IncognitoReauthObserver>)observer;
+- (void)removeObserver:(id<IncognitoReauthObserver>)observer;
+
 @end
 
 #endif  // IOS_CHROME_BROWSER_UI_INCOGNITO_REAUTH_INCOGNITO_REAUTH_SCENE_AGENT_H_

ios/chrome/browser/ui/incognito_reauth/incognito_reauth_scene_agent.mm

@@ -5,6 +5,7 @@
 #import "ios/chrome/browser/ui/incognito_reauth/incognito_reauth_scene_agent.h"
 
 #include "base/check.h"
+#import "base/ios/crb_protocol_observers.h"
 #include "components/pref_registry/pref_registry_syncable.h"
 #include "components/prefs/pref_service.h"
 #include "ios/chrome/browser/application_context.h"
@@ -19,6 +20,14 @@
 #error "This file requires ARC support."
 #endif
 
+@interface IncognitoReauthObserverList
+    : CRBProtocolObservers <IncognitoReauthObserver>
+@end
+@implementation IncognitoReauthObserverList
+@end
+
+#pragma mark - IncognitoReauthSceneAgent
+
 @interface IncognitoReauthSceneAgent () <SceneStateObserver>
 
 // Scene state this agent serves.
@@ -30,6 +39,9 @@
 // Tracks wether the user authenticated for incognito since last launch.
 @property(nonatomic, assign) BOOL authenticatedSinceLastForeground;
 
+// Container for observers.
+@property(nonatomic, strong) IncognitoReauthObserverList* observers;
+
 @end
 
 @implementation IncognitoReauthSceneAgent
@@ -48,14 +60,14 @@
   if (self) {
     DCHECK(reauthModule);
     _reauthModule = reauthModule;
+    _observers = [IncognitoReauthObserverList
+        observersWithProtocol:@protocol(IncognitoReauthObserver)];
   }
   return self;
 }
 
 - (BOOL)isAuthenticationRequired {
-  return base::FeatureList::IsEnabled(kIncognitoAuthentication) &&
-         [self authEnabledInSettings] &&
-         self.windowHadIncognitoContentOnForeground &&
+  return [self featureEnabled] && self.windowHadIncognitoContentOnForeground &&
          !self.authenticatedSinceLastForeground;
 }
 
@@ -87,6 +99,36 @@
                                }];
 }
 
+- (void)addObserver:(id<IncognitoReauthObserver>)observer {
+  [self.observers addObserver:observer];
+}
+
+- (void)removeObserver:(id<IncognitoReauthObserver>)observer {
+  [self.observers removeObserver:observer];
+}
+
+#pragma mark properties
+
+- (void)setAuthenticatedSinceLastForeground:(BOOL)authenticated {
+  _authenticatedSinceLastForeground = authenticated;
+  if (self.featureEnabled) {
+    [self notifyObservers];
+  }
+}
+
+- (void)setWindowHadIncognitoContentOnForeground:(BOOL)hadIncognitoContent {
+  _windowHadIncognitoContentOnForeground = hadIncognitoContent;
+  if (self.featureEnabled) {
+    [self notifyObservers];
+  }
+}
+
+- (void)notifyObservers {
+  DCHECK(self.featureEnabled);
+  [self.observers reauthAgent:self
+      didUpdateAuthenticationRequirement:self.isAuthenticationRequired];
+}
+
 #pragma mark - SceneStateObserver
 
 - (void)sceneState:(SceneState*)sceneState
@@ -119,14 +161,21 @@
 
 - (PrefService*)localState {
   if (!_localState) {
+    if (!GetApplicationContext()) {
+      // This is called before application context was initialized.
+      return nil;
+    }
     _localState = GetApplicationContext()->GetLocalState();
   }
   return _localState;
 }
 
-// Convenience method to check the pref associated with the reauth setting.
-- (BOOL)authEnabledInSettings {
-  return self.localState->GetBoolean(prefs::kIncognitoAuthenticationSetting);
+// Convenience method to check the pref associated with the reauth setting and
+// the feature flag.
+- (BOOL)featureEnabled {
+  return base::FeatureList::IsEnabled(kIncognitoAuthentication) &&
+         self.localState &&
+         self.localState->GetBoolean(prefs::kIncognitoAuthenticationSetting);
 }
 
 @end

ios/chrome/browser/ui/incognito_reauth/incognito_reauth_view.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_INCOGNITO_REAUTH_INCOGNITO_REAUTH_VIEW_H_
+#define IOS_CHROME_BROWSER_UI_INCOGNITO_REAUTH_INCOGNITO_REAUTH_VIEW_H_
+
+#import <UIKit/UIKit.h>
+
+// The view that is used to overlay over non-authorized incognito content.
+@interface IncognitoReauthView : UIView
+
+// Button that allows biometric authentication.
+// Will auto-adjust its string based on the available authentication methods on
+// the user's device.
+@property(nonatomic, strong, readonly) UIButton* authenticateButton;
+// The button to go to the tab switcher.
+@property(nonatomic, strong, readonly) UIButton* tabSwitcherButton;
+
+@end
+
+#endif  // IOS_CHROME_BROWSER_UI_INCOGNITO_REAUTH_INCOGNITO_REAUTH_VIEW_H_

ios/chrome/browser/ui/incognito_reauth/incognito_reauth_view.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/incognito_reauth/incognito_reauth_view.h"
+
+#import <LocalAuthentication/LocalAuthentication.h>
+
+#import "ios/chrome/common/ui/util/constraints_ui_util.h"
+
+#if !defined(__has_feature) || !__has_feature(objc_arc)
+#error "This file requires ARC support."
+#endif
+
+namespace {
+const CGFloat kButtonHeight = 60.0f;
+const CGFloat kButtonWidth = 190.0f;
+const CGFloat kButtonSpacing = 16.0f;
+}  // namespace
+
+@implementation IncognitoReauthView
+
+- (instancetype)init {
+  self = [super init];
+  if (self) {
+    UIBlurEffect* blurEffect =
+        [UIBlurEffect effectWithStyle:UIBlurEffectStyleDark];
+    UIVisualEffectView* blurBackgroundView =
+        [[UIVisualEffectView alloc] initWithEffect:blurEffect];
+    [self addSubview:blurBackgroundView];
+    blurBackgroundView.translatesAutoresizingMaskIntoConstraints = NO;
+    AddSameConstraints(self, blurBackgroundView);
+
+    _authenticateButton =
+        [IncognitoReauthView newRoundButtonWithBlurEffect:blurEffect];
+    [_authenticateButton
+        setTitle:[IncognitoReauthView authenticationActionLabel]
+        forState:UIControlStateNormal];
+
+    _tabSwitcherButton =
+        [IncognitoReauthView newRoundButtonWithBlurEffect:blurEffect];
+    // TODO(crbug.com/1138892): add localized text.
+    [_tabSwitcherButton setTitle:@"[Test String] Go to Tab Switcher"
+                        forState:UIControlStateNormal];
+
+    UIStackView* stackView = [[UIStackView alloc]
+        initWithArrangedSubviews:@[ _authenticateButton, _tabSwitcherButton ]];
+    stackView.axis = UILayoutConstraintAxisVertical;
+    stackView.translatesAutoresizingMaskIntoConstraints = NO;
+    stackView.spacing = kButtonSpacing;
+    [self addSubview:stackView];
+    AddSameCenterConstraints(blurBackgroundView, stackView);
+  }
+
+  return self;
+}
+
++ (NSString*)authenticationActionLabel {
+  LAContext* ctx = [[LAContext alloc] init];
+  switch (ctx.biometryType) {
+    case LABiometryTypeFaceID:
+      return @"Face ID";
+    case LABiometryTypeTouchID:
+      return @"Touch ID";
+    default:
+      // TODO(crbug.com/1138892): add localized text.
+      return @"[Test String] Passcode";
+  }
+}
+
++ (UIButton*)newRoundButtonWithBlurEffect:(UIBlurEffect*)blurEffect {
+  UIButton* button = [[UIButton alloc] init];
+  button.backgroundColor = [UIColor clearColor];
+
+  [NSLayoutConstraint activateConstraints:@[
+    [button.heightAnchor constraintEqualToConstant:kButtonHeight],
+    [button.widthAnchor constraintEqualToConstant:kButtonWidth],
+  ]];
+
+  UIView* backgroundView = nil;
+  if (@available(iOS 13, *)) {
+    backgroundView = [[UIVisualEffectView alloc]
+        initWithEffect:[UIVibrancyEffect
+                           effectForBlurEffect:blurEffect
+                                         style:UIVibrancyEffectStyleFill]];
+  } else {
+    backgroundView = [[UIView alloc] init];
+  }
+  backgroundView.backgroundColor = [UIColor colorWithWhite:1 alpha:0.2];
+  backgroundView.layer.cornerRadius = kButtonHeight / 2;
+  backgroundView.translatesAutoresizingMaskIntoConstraints = NO;
+  [button addSubview:backgroundView];
+  AddSameConstraints(backgroundView, button);
+
+  return button;
+}
+
+@end

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

@@ -273,13 +273,11 @@ const char kMultiWindowOpenInNewWindowHistogram[] =
     // Add agents.
     [_sceneState addAgent:[[UIBlockerSceneAgent alloc] init]];
     [_sceneState addAgent:[[IncognitoBlockerSceneAgent alloc] init]];
-    if (base::FeatureList::IsEnabled(kIncognitoAuthentication)) {
     [_sceneState
         addAgent:[[IncognitoReauthSceneAgent alloc]
                      initWithReauthModule:[[ReauthenticationModule alloc]
                                               init]]];
   }
-  }
   return self;
 }
 

ios/chrome/browser/ui/tab_switcher/tab_grid/BUILD.gn

@@ -41,6 +41,7 @@ source_set("tab_grid") {
     "//ios/chrome/browser/ui/gestures",
     "//ios/chrome/browser/ui/history",
     "//ios/chrome/browser/ui/history/public",
+    "//ios/chrome/browser/ui/incognito_reauth:incognito_reauth_scene_agent",
     "//ios/chrome/browser/ui/main",
     "//ios/chrome/browser/ui/recent_tabs",
     "//ios/chrome/browser/ui/recent_tabs:recent_tabs_ui",
@@ -164,6 +165,7 @@ source_set("unit_tests") {
     "//ios/chrome/browser/tabs",
     "//ios/chrome/browser/tabs:tabs_internal",
     "//ios/chrome/browser/ui/commands",
+    "//ios/chrome/browser/ui/main:scene_state_header",
     "//ios/chrome/browser/ui/tab_switcher",
     "//ios/chrome/browser/web",
     "//ios/chrome/browser/web:page_placeholder",

ios/chrome/browser/ui/tab_switcher/tab_grid/grid/BUILD.gn

@@ -53,6 +53,7 @@ source_set("grid_ui") {
     "//ios/chrome/browser/ui:feature_flags",
     "//ios/chrome/browser/ui/elements",
     "//ios/chrome/browser/ui/gestures",
+    "//ios/chrome/browser/ui/incognito_reauth:incognito_reauth_ui",
     "//ios/chrome/browser/ui/tab_switcher",
     "//ios/chrome/browser/ui/tab_switcher/tab_grid/transitions",
     "//ios/chrome/browser/ui/thumb_strip:feature_flags",

ios/chrome/browser/ui/tab_switcher/tab_grid/grid/grid_consumer.h

@@ -12,6 +12,10 @@
 // Supports idempotent insert/delete/updates to a grid.
 @protocol GridConsumer
 
+// Notify consumer that the displayed items require authentication before they
+// can be accessed. Used for biometric incognito tab authentication.
+- (void)setItemsRequireAuthentication:(BOOL)requireAuthentication;
+
 // Many of the following methods pass a |selectedItemID| as a parameter,
 // indicating the identifier of the item that should be in the selected state
 // after the method is called. In every such case, a nil |selectedItemID|

ios/chrome/browser/ui/tab_switcher/tab_grid/grid/grid_view_controller.h

@@ -45,6 +45,11 @@
 - (void)didChangeLastItemVisibilityInGridViewController:
     (GridViewController*)gridViewController;
 
+// Tells the delegate when the currently displayed content is hidden from the
+// user until they authenticate. Used for incognito biometric authentication.
+- (void)gridViewController:(GridViewController*)gridViewController
+    contentNeedsAuthenticationChanged:(BOOL)needsAuth;
+
 @end
 
 // A view controller that contains a grid of items.
@@ -71,6 +76,9 @@
 @property(nonatomic, assign) BOOL showsSelectionUpdates;
 // The fraction of the last item of the grid that is visible.
 @property(nonatomic, assign, readonly) CGFloat fractionVisibleOfLastItem;
+// YES when the current contents are hidden from the user before a successful
+// biometric authentication.
+@property(nonatomic, assign) BOOL contentNeedsAuthentication;
 
 // Returns the layout of the grid for use in an animated transition.
 - (GridTransitionLayout*)transitionLayout;

ios/chrome/browser/ui/tab_switcher/tab_grid/grid/grid_view_controller.mm

@@ -15,6 +15,7 @@
 #import "base/numerics/safe_conversions.h"
 #include "ios/chrome/browser/drag_and_drop/drag_and_drop_flag.h"
 #include "ios/chrome/browser/procedural_block_types.h"
+#import "ios/chrome/browser/ui/incognito_reauth/incognito_reauth_view.h"
 #import "ios/chrome/browser/ui/tab_switcher/tab_grid/grid/grid_cell.h"
 #import "ios/chrome/browser/ui/tab_switcher/tab_grid/grid/grid_constants.h"
 #import "ios/chrome/browser/ui/tab_switcher/tab_grid/grid/grid_drag_drop_handler.h"
@@ -56,6 +57,9 @@ NSIndexPath* CreateIndexPath(NSInteger index) {
                                   UICollectionViewDropDelegate>
 // A collection view of items in a grid format.
 @property(nonatomic, weak) UICollectionView* collectionView;
+// A view to obscure incognito content when the user isn't authorized to
+// see it.
+@property(nonatomic, strong) IncognitoReauthView* blockingView;
 // The local model backing the collection view.
 @property(nonatomic, strong) NSMutableArray<TabSwitcherItem*>* items;
 // Identifier of the selected item. This value is disregarded if |self.items| is
@@ -614,6 +618,27 @@ NSIndexPath* CreateIndexPath(NSInteger index) {
 
 #pragma mark - GridConsumer
 
+- (void)setItemsRequireAuthentication:(BOOL)require {
+  self.contentNeedsAuthentication = require;
+  [self.delegate gridViewController:self
+      contentNeedsAuthenticationChanged:require];
+
+  if (require) {
+    if (!self.blockingView) {
+      self.blockingView = [[IncognitoReauthView alloc] init];
+      self.blockingView.translatesAutoresizingMaskIntoConstraints = NO;
+      self.blockingView.layer.zPosition = FLT_MAX;
+      // No need to show tab switcher button when already in the tab switcher.
+      self.blockingView.tabSwitcherButton.hidden = YES;
+    }
+
+    [self.view addSubview:self.blockingView];
+    AddSameConstraints(self.collectionView.frameLayoutGuide, self.blockingView);
+  } else {
+    [self.blockingView removeFromSuperview];
+  }
+}
+
 - (void)populateItems:(NSArray<TabSwitcherItem*>*)items
        selectedItemID:(NSString*)selectedItemID {
 #ifndef NDEBUG

ios/chrome/browser/ui/tab_switcher/tab_grid/grid/grid_view_controller_unittest.mm

@@ -31,6 +31,10 @@
 @end
 @implementation FakeGridViewControllerDelegate
 @synthesize itemCount = _itemCount;
+
+- (void)gridViewController:(GridViewController*)gridViewController
+    contentNeedsAuthenticationChanged:(BOOL)needsAuth {
+}
 - (void)gridViewController:(GridViewController*)gridViewController
         didChangeItemCount:(NSUInteger)count {
   self.itemCount = count;

ios/chrome/browser/ui/tab_switcher/tab_grid/tab_grid_bottom_toolbar.h

@@ -35,6 +35,8 @@
 
 // Sets target/action for tapping event on new tab button.
 - (void)setNewTabButtonTarget:(id)target action:(SEL)action;
+// Set |enabled| on the new tab button.
+- (void)setNewTabButtonEnabled:(BOOL)enabled;
 
 // Hides components and uses a black background color for tab grid transition
 // animation.

ios/chrome/browser/ui/tab_switcher/tab_grid/tab_grid_bottom_toolbar.mm

@@ -86,6 +86,11 @@
                forControlEvents:UIControlEventTouchUpInside];
 }
 
+- (void)setNewTabButtonEnabled:(BOOL)enabled {
+  _smallNewTabButton.enabled = enabled;
+  _largeNewTabButton.enabled = enabled;
+}
+
 - (void)hide {
   _smallNewTabButton.alpha = 0.0;
   _largeNewTabButton.alpha = 0.0;

ios/chrome/browser/ui/tab_switcher/tab_grid/tab_grid_coordinator.mm

@@ -25,7 +25,9 @@
 #import "ios/chrome/browser/ui/gestures/view_revealing_vertical_pan_handler.h"
 #import "ios/chrome/browser/ui/history/history_coordinator.h"
 #import "ios/chrome/browser/ui/history/public/history_presentation_delegate.h"
+#import "ios/chrome/browser/ui/incognito_reauth/incognito_reauth_scene_agent.h"
 #import "ios/chrome/browser/ui/main/bvc_container_view_controller.h"
+#import "ios/chrome/browser/ui/main/scene_state_browser_agent.h"
 #import "ios/chrome/browser/ui/recent_tabs/recent_tabs_mediator.h"
 #import "ios/chrome/browser/ui/recent_tabs/recent_tabs_menu_helper.h"
 #import "ios/chrome/browser/ui/recent_tabs/recent_tabs_presentation_delegate.h"
@@ -309,7 +311,8 @@
   _baseViewController = baseViewController;
 
   self.regularTabsMediator = [[TabGridMediator alloc]
-      initWithConsumer:baseViewController.regularTabsConsumer];
+      initWithConsumer:baseViewController.regularTabsConsumer
+           reauthAgent:nil];
   ChromeBrowserState* regularBrowserState =
       _regularBrowser ? _regularBrowser->GetBrowserState() : nullptr;
   WebStateList* regularWebStateList =
@@ -322,8 +325,19 @@
         IOSChromeTabRestoreServiceFactory::GetForBrowserState(
             regularBrowserState);
   }
+
+  IncognitoReauthSceneAgent* reauthAgent = nil;
+  for (id agent in SceneStateBrowserAgent::FromBrowser(_incognitoBrowser)
+           ->GetSceneState()
+           .connectedAgents) {
+    if ([agent isKindOfClass:[IncognitoReauthSceneAgent class]]) {
+      reauthAgent = agent;
+    }
+  }
+
   self.incognitoTabsMediator = [[TabGridMediator alloc]
-      initWithConsumer:baseViewController.incognitoTabsConsumer];
+      initWithConsumer:baseViewController.incognitoTabsConsumer
+           reauthAgent:reauthAgent];
   self.incognitoTabsMediator.browser = _incognitoBrowser;
   self.incognitoTabsMediator.delegate = self;
   baseViewController.regularTabsDelegate = self.regularTabsMediator;

ios/chrome/browser/ui/tab_switcher/tab_grid/tab_grid_coordinator_unittest.mm

@@ -12,6 +12,8 @@
 #import "ios/chrome/browser/snapshots/snapshot_browser_agent.h"
 #import "ios/chrome/browser/ui/commands/application_commands.h"
 #import "ios/chrome/browser/ui/commands/browsing_data_commands.h"
+#import "ios/chrome/browser/ui/main/scene_state.h"
+#import "ios/chrome/browser/ui/main/scene_state_browser_agent.h"
 #include "ios/chrome/browser/ui/tab_switcher/tab_grid/tab_grid_coordinator_delegate.h"
 #import "ios/chrome/test/block_cleanup_test.h"
 #include "ios/web/public/test/web_task_environment.h"
@@ -22,6 +24,20 @@
 #error "This file requires ARC support."
 #endif
 
+@interface StubSceneState : SceneState
+@end
+
+@implementation StubSceneState {
+  UIWindow* _window;
+}
+- (void)setWindow:(UIWindow*)window {
+  _window = window;
+}
+- (UIWindow*)window {
+  return _window;
+}
+@end
+
 @interface TestTabGridCoordinatorDelegate
     : NSObject <TabGridCoordinatorDelegate>
 @property(nonatomic) BOOL didEndCalled;
@@ -42,13 +58,25 @@
 
 namespace {
 
+void AddAgentsToBrowser(Browser* browser, SceneState* scene_state) {
+  SnapshotBrowserAgent::CreateForBrowser(browser);
+  SnapshotBrowserAgent::FromBrowser(browser)->SetSessionID(
+      base::SysNSStringToUTF8([[NSUUID UUID] UUIDString]));
+  SceneStateBrowserAgent::CreateForBrowser(browser, scene_state);
+}
+
 class TabGridCoordinatorTest : public BlockCleanupTest {
  public:
   TabGridCoordinatorTest() {
+    scene_state_ = [[StubSceneState alloc] initWithAppState:nil];
+    scene_state_.window =
+        [[UIApplication sharedApplication].windows firstObject];
+
     browser_ = std::make_unique<TestBrowser>();
-    SnapshotBrowserAgent::CreateForBrowser(browser_.get());
-    SnapshotBrowserAgent::FromBrowser(browser_.get())
-        ->SetSessionID(base::SysNSStringToUTF8([[NSUUID UUID] UUIDString]));
+    AddAgentsToBrowser(browser_.get(), scene_state_);
+
+    incognito_browser_ = std::make_unique<TestBrowser>();
+    AddAgentsToBrowser(incognito_browser_.get(), scene_state_);
 
     UIWindow* window = [UIApplication sharedApplication].keyWindow;
     coordinator_ = [[TabGridCoordinator alloc]
@@ -58,7 +86,7 @@ class TabGridCoordinatorTest : public BlockCleanupTest {
         browsingDataCommandEndpoint:OCMProtocolMock(
                                         @protocol(BrowsingDataCommands))
                      regularBrowser:browser_.get()
-                   incognitoBrowser:nil];
+                   incognitoBrowser:incognito_browser_.get()];
     coordinator_.animationsDisabledForTesting = YES;
     // TabGirdCoordinator will make its view controller the root, so stash the
     // original root view controller before starting |coordinator_|.
@@ -93,6 +121,12 @@ class TabGridCoordinatorTest : public BlockCleanupTest {
   // Browser for the coordinator.
   std::unique_ptr<Browser> browser_;
 
+  // Browser for the coordinator.
+  std::unique_ptr<Browser> incognito_browser_;
+
+  // Scene state emulated in this test.
+  SceneState* scene_state_;
+
   // The TabGridCoordinator that is under test.  The test fixture sets
   // this VC as the root VC for the window.
   TabGridCoordinator* coordinator_;

ios/chrome/browser/ui/tab_switcher/tab_grid/tab_grid_mediator.h

@@ -13,6 +13,7 @@
 
 class Browser;
 @protocol GridConsumer;
+@class IncognitoReauthSceneAgent;
 @class TabGridMediator;
 
 namespace sessions {
@@ -47,6 +48,7 @@ class TabRestoreService;
 
 // Initializer with |consumer| as the receiver of model layer updates.
 - (instancetype)initWithConsumer:(id<GridConsumer>)consumer
+                     reauthAgent:(IncognitoReauthSceneAgent*)reauthAgent
     NS_DESIGNATED_INITIALIZER;
 - (instancetype)init NS_UNAVAILABLE;
 @end

ios/chrome/browser/ui/tab_switcher/tab_grid/tab_grid_mediator.mm

@@ -28,6 +28,7 @@
 #import "ios/chrome/browser/snapshots/snapshot_tab_helper.h"
 #include "ios/chrome/browser/system_flags.h"
 #import "ios/chrome/browser/tabs/tab_title_util.h"
+#import "ios/chrome/browser/ui/incognito_reauth/incognito_reauth_scene_agent.h"
 #import "ios/chrome/browser/ui/tab_switcher/tab_grid/grid/grid_consumer.h"
 #import "ios/chrome/browser/ui/tab_switcher/tab_switcher_item.h"
 #import "ios/chrome/browser/web/tab_id_tab_helper.h"
@@ -109,6 +110,7 @@ web::WebState* GetWebStateWithId(WebStateList* web_state_list,
 }  // namespace
 
 @interface TabGridMediator () <CRWWebStateObserver,
+                               IncognitoReauthObserver,
                                SnapshotCacheObserver,
                                WebStateListObserving>
 // The list from the browser.
@@ -125,6 +127,8 @@ web::WebState* GetWebStateWithId(WebStateList* web_state_list,
 // Short-term cache for grid thumbnails.
 @property(nonatomic, strong)
     NSMutableDictionary<NSString*, UIImage*>* appearanceCache;
+// Agent tracking the authentication status.
+@property(nonatomic, weak) IncognitoReauthSceneAgent* reauthAgent;
 @end
 
 @implementation TabGridMediator {
@@ -138,7 +142,8 @@ web::WebState* GetWebStateWithId(WebStateList* web_state_list,
       _scopedWebStateObserver;
 }
 
-- (instancetype)initWithConsumer:(id<GridConsumer>)consumer {
+- (instancetype)initWithConsumer:(id<GridConsumer>)consumer
+                     reauthAgent:(IncognitoReauthSceneAgent*)agent {
   if (self = [super init]) {
     _consumer = consumer;
     _webStateListObserverBridge =
@@ -152,6 +157,8 @@ web::WebState* GetWebStateWithId(WebStateList* web_state_list,
         std::make_unique<ScopedObserver<web::WebState, web::WebStateObserver>>(
             _webStateObserverBridge.get());
     _appearanceCache = [[NSMutableDictionary alloc] init];
+    _reauthAgent = agent;
+    [agent addObserver:self];
   }
   return self;
 }
@@ -557,6 +564,13 @@ web::WebState* GetWebStateWithId(WebStateList* web_state_list,
   [self.appearanceCache removeAllObjects];
 }
 
+#pragma mark - IncognitoReauthObserver
+
+- (void)reauthAgent:(IncognitoReauthSceneAgent*)agent
+    didUpdateAuthenticationRequirement:(BOOL)isRequired {
+  [self.consumer setItemsRequireAuthentication:isRequired];
+}
+
 #pragma mark - Private
 
 // Calls |-populateItems:selectedItemID:| on the consumer.
@@ -565,6 +579,9 @@ web::WebState* GetWebStateWithId(WebStateList* web_state_list,
     [self.consumer populateItems:CreateItems(self.webStateList)
                   selectedItemID:GetActiveTabId(self.webStateList)];
   }
+
+  [self.consumer
+      setItemsRequireAuthentication:self.reauthAgent.authenticationRequired];
 }
 
 // Removes |self.syncedClosedTabsCount| most recent entries from the

ios/chrome/browser/ui/tab_switcher/tab_grid/tab_grid_mediator_unittest.mm

@@ -161,6 +161,10 @@ std::unique_ptr<KeyedService> BuildFakeTabRestoreService(
 @synthesize items = _items;
 @synthesize selectedItemID = _selectedItemID;
 
+- (void)setItemsRequireAuthentication:(BOOL)require {
+  // No-op.
+}
+
 - (void)populateItems:(NSArray<TabSwitcherItem*>*)items
        selectedItemID:(NSString*)selectedItemID {
   self.selectedItemID = selectedItemID;
@@ -264,7 +268,8 @@ class TabGridMediatorTest : public PlatformTest {
         TabIdTabHelper::FromWebState(web_state_list_->GetWebStateAt(1))
             ->tab_id();
     consumer_ = [[FakeConsumer alloc] init];
-    mediator_ = [[TabGridMediator alloc] initWithConsumer:consumer_];
+    mediator_ = [[TabGridMediator alloc] initWithConsumer:consumer_
+                                              reauthAgent:nil];
     mediator_.browser = browser_.get();
     mediator_.tabRestoreService = tab_restore_service_;
   }

ios/chrome/browser/ui/tab_switcher/tab_grid/tab_grid_view_controller.mm

@@ -991,6 +991,15 @@ NSUInteger GetPageIndexFromPage(TabGridPage page) {
     [self configureDoneButtonBasedOnPage:self.currentPage];
   }
   [self configureCloseAllButtonForCurrentPageAndUndoAvailability];
+
+  [self configureNewTabButtonBasedOnContentPermissions];
+}
+
+- (void)configureNewTabButtonBasedOnContentPermissions {
+  BOOL allowNewTab =
+      !((self.currentPage == TabGridPageIncognitoTabs) &&
+        self.incognitoTabsViewController.contentNeedsAuthentication);
+  [self.bottomToolbar setNewTabButtonEnabled:allowNewTab];
 }
 
 - (void)configureDoneButtonBasedOnPage:(TabGridPage)page {
@@ -1002,8 +1011,14 @@ NSUInteger GetPageIndexFromPage(TabGridPage page) {
   }
   // The Done button should have the same behavior as the other buttons on the
   // top Toolbar.
-  self.doneButton.enabled = !gridViewController.gridEmpty &&
-                            self.topToolbar.pageControl.userInteractionEnabled;
+  BOOL incognitoTabsNeedsAuth =
+      (self.currentPage == TabGridPageIncognitoTabs &&
+       self.incognitoTabsViewController.contentNeedsAuthentication);
+
+  self.doneButton.enabled =
+      !gridViewController.gridEmpty &&
+      self.topToolbar.pageControl.userInteractionEnabled &&
+      !incognitoTabsNeedsAuth;
 }
 
 - (void)configureCloseAllButtonForCurrentPageAndUndoAvailability {
@@ -1020,8 +1035,14 @@ NSUInteger GetPageIndexFromPage(TabGridPage page) {
   // Otherwise setup as a Close All button.
   GridViewController* gridViewController =
       [self gridViewControllerForPage:self.currentPage];
-  self.closeAllButton.enabled =
-      gridViewController == nil ? NO : !gridViewController.gridEmpty;
+  BOOL enabled =
+      (gridViewController == nil) ? NO : !gridViewController.gridEmpty;
+  BOOL incognitoTabsNeedsAuth =
+      (self.currentPage == TabGridPageIncognitoTabs &&
+       self.incognitoTabsViewController.contentNeedsAuthentication);
+  enabled = enabled && !incognitoTabsNeedsAuth;
+
+  self.closeAllButton.enabled = enabled;
   self.closeAllButton.title =
       l10n_util::GetNSString(IDS_IOS_TAB_GRID_CLOSE_ALL_BUTTON);
   // Setting the |accessibilityIdentifier| seems to trigger layout, which causes
@@ -1386,6 +1407,11 @@ NSUInteger GetPageIndexFromPage(TabGridPage page) {
           : CGAffineTransformIdentity;
 }
 
+- (void)gridViewController:(GridViewController*)gridViewController
+    contentNeedsAuthenticationChanged:(BOOL)needsAuth {
+  [self configureButtonsForActiveAndCurrentPage];
+}
+
 #pragma mark - Control actions
 
 - (void)doneButtonTapped:(id)sender {