Fix flaky NewTabPageTestCase.testOmnibox

ios/chrome/browser/ui/ntp/google_landing_controller.mm

Index: ios/chrome/browser/ui/ntp/google_landing_controller.mm
diff --git a/ios/chrome/browser/ui/ntp/google_landing_controller.mm b/ios/chrome/browser/ui/ntp/google_landing_controller.mm
index 47be94d11c170ec9f3e283eaff81a8e0413030f7..2e59132647a2eda4df229d1ee9b0867c6bd0e182 100644
--- a/ios/chrome/browser/ui/ntp/google_landing_controller.mm
+++ b/ios/chrome/browser/ui/ntp/google_landing_controller.mm
@@ -1674,10 +1674,16 @@ void SearchEngineObserver::OnTemplateURLServiceChanged() {
   _most_visited_sites->AddOrRemoveBlacklistedUrl(url, false);
 }
 
+#pragma mark - GoogleLandingController (ExposedForTesting) methods.
+
 - (BOOL)scrolledToTop {
   return _scrolledToTop;
 }
 
+- (BOOL)animateHeader {
+  return _animateHeader;
+}
+
 #pragma mark - OverscrollActionsControllerDelegate
 
 - (void)overscrollActionsController:(OverscrollActionsController*)controller