[iOS] Scrolling between the initial and expand states is jumpy

Issue for the payments bottom sheet was caused by recalculating the
initial height every time -viewIsAppearing is called.

Keeping track of the value and reusing it fixed this issue.

Bug: 1469913
Change-Id: I64941cc7dc80473c3dd8414e0aa091be5f50037b
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/4771062
Reviewed-by: Tommy Martino <tmartino@chromium.org>
Commit-Queue: Veronique Nguyen <veronguyen@google.com>
Code-Coverage: findit-for-me@appspot.gserviceaccount.com <findit-for-me@appspot.gserviceaccount.com>
Cr-Commit-Position: refs/heads/main@{#1182618}

ios/chrome/browser/ui/autofill/bottom_sheet/payments_suggestion_bottom_sheet_view_controller.mm

@@ -74,6 +74,9 @@ @interface PaymentsSuggestionBottomSheetViewController () <
 // YES if the expanded bottom sheet size takes the whole screen.
 @property(nonatomic, assign) BOOL expandSizeTooLarge;
 
+// Keep track of the minimized state height.
+@property(nonatomic, assign) absl::optional<CGFloat> minimizedStateHeight;
+
 @end
 
 @implementation PaymentsSuggestionBottomSheetViewController
@@ -133,6 +136,7 @@ - (void)traitCollectionDidChange:(UITraitCollection*)previousTraitCollection {
 
   if (self.traitCollection.preferredContentSizeCategory !=
       previousTraitCollection.preferredContentSizeCategory) {
+    self.minimizedStateHeight = absl::nullopt;
     [self updateHeight];
   }
 }
@@ -152,6 +156,13 @@ - (void)viewDidDisappear:(BOOL)animated {
   [self.handler viewDidDisappear:animated];
 }
 
+- (CGFloat)initialHeight {
+  if (!self.minimizedStateHeight.has_value()) {
+    self.minimizedStateHeight = [super initialHeight];
+  }
+  return self.minimizedStateHeight.value();
+}
+
 #pragma mark - PaymentsSuggestionBottomSheetConsumer
 
 - (void)setCreditCardData: