[iOS] Fix 13.5 ConfirmationAlertViewController Toolbar Done Button

When going from compact width to regular width, we swap the toolbar
buttons. This allows us to add/remove buttons based on the screen
constraints. Before iOS 13.5, setting the "items" property of a
UIToolbar worked fine. However, in 13.5, this made the last button
(Done button) to become non-responsive when going from compact width
to regular width.

Somehow, using the setItems:animated API fixes the issue.

Tested on simulators:
iPhone 13.5 and 12.4
iPAD 13.5 and 12.4

Bug: 1082723
Change-Id: Icde5b6760038560f9f8601af1afc328a4e2e4aae
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2216285
Commit-Queue: Javier Ernesto Flores Robles <javierrobles@chromium.org>
Reviewed-by: Javier Ernesto Flores Robles <javierrobles@chromium.org>
Auto-Submit: Sebastien Lalancette <seblalancette@chromium.org>
Cr-Commit-Position: refs/heads/master@{#772160}

ios/chrome/common/ui/confirmation_alert/confirmation_alert_view_controller.mm

@@ -265,11 +265,17 @@ constexpr CGFloat kSafeAreaMultiplier = 0.8;
   if (isVerticalCompact) {
     oldBottomConstraint = self.regularHeightScrollViewBottomVerticalConstraint;
     newBottomConstraint = self.compactHeightScrollViewBottomVerticalConstraint;
-    self.topToolbar.items = self.compactHeightToolbarItems;
+
+    // Use setItems:animated method instead of setting the items property, as
+    // that causes issues with the Done button. See crbug.com/1082723
+    [self.topToolbar setItems:self.compactHeightToolbarItems animated:YES];
   } else {
     oldBottomConstraint = self.compactHeightScrollViewBottomVerticalConstraint;
     newBottomConstraint = self.regularHeightScrollViewBottomVerticalConstraint;
-    self.topToolbar.items = self.regularHeightToolbarItems;
+
+    // Use setItems:animated method instead of setting the items property, as
+    // that causes issues with the Done button. See crbug.com/1082723
+    [self.topToolbar setItems:self.regularHeightToolbarItems animated:YES];
   }
 
   newBottomConstraint.constant = -marginValue;