[iOS] Disables top toolbar when Close All Tabs Confirmation is displayed

This CL disables the top toolbar of the tab grid  the 'Close All Tabs'
Confirmation action sheet is displayed.

Bug: 1140518
Change-Id: I6e6d8f5103554e79b40f7ab1cdb8e962e43822a4
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2502478
Commit-Queue: Ewann Pellé <ewannpv@chromium.org>
Reviewed-by: Mark Cogan <marq@chromium.org>
Cr-Commit-Position: refs/heads/master@{#822091}

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

@@ -476,6 +476,8 @@
 
   self.actionSheetCoordinator.alertStyle = UIAlertControllerStyleActionSheet;
 
+  __weak TabGridCoordinator* weakSelf = self;
+
   [self.actionSheetCoordinator
       addItemWithTitle:base::SysUTF16ToNSString(
                            l10n_util::GetPluralStringFUTF16(
@@ -485,6 +487,7 @@
                   base::RecordAction(base::UserMetricsAction(
                       "MobileTabGridCloseAllTabsConfirmationConfirmed"));
                   [tabGridMediator closeAllItems];
+                  [weakSelf.baseViewController closeAllTabsConfirmationClosed];
                 }
                  style:UIAlertActionStyleDestructive];
   [self.actionSheetCoordinator
@@ -492,6 +495,7 @@
                 action:^{
                   base::RecordAction(base::UserMetricsAction(
                       "MobileTabGridCloseAllTabsConfirmationCanceled"));
+                  [weakSelf.baseViewController closeAllTabsConfirmationClosed];
                 }
                  style:UIAlertActionStyleCancel];
   [self.actionSheetCoordinator start];

ios/chrome/browser/ui/tab_grid/tab_grid_view_controller.h

@@ -80,6 +80,10 @@
 - (void)contentDidAppear;
 - (void)contentWillDisappearAnimated:(BOOL)animated;
 
+// Notifies the ViewController that the Close All Tabs confirmation action sheet
+// has been closed.
+- (void)closeAllTabsConfirmationClosed;
+
 @end
 
 #endif  // IOS_CHROME_BROWSER_UI_TAB_GRID_TAB_GRID_VIEW_CONTROLLER_H_

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

@@ -401,6 +401,10 @@ NSUInteger GetPageIndexFromPage(TabGridPage page) {
   self.remoteTabsViewController.preventUpdates = YES;
 }
 
+- (void)closeAllTabsConfirmationClosed {
+  self.topToolbar.pageControl.userInteractionEnabled = YES;
+}
+
 #pragma mark - Public Properties
 
 - (id<GridConsumer>)regularTabsConsumer {
@@ -1329,7 +1333,7 @@ NSUInteger GetPageIndexFromPage(TabGridPage page) {
   // toolbar in order to avoid alignment issues when changing the device
   // orientation to landscape in multi window mode.
   UIBarButtonItem* buttonAnchor = self.topToolbar.leadingButton;
-
+  self.topToolbar.pageControl.userInteractionEnabled = NO;
   switch (self.currentPage) {
     case TabGridPageIncognitoTabs:
       [self.incognitoTabsDelegate