[iOS] We need to reload the datasource to show unevenrows

Xamarin.Forms.Platform.iOS/Renderers/ListViewRenderer.cs

@@ -263,6 +263,7 @@ namespace Xamarin.Forms.Platform.iOS
 			{
 				_estimatedRowHeight = false;
 				Control.Source = _dataSource = Element.HasUnevenRows ? new UnevenListViewDataSource(_dataSource) : new ListViewDataSource(_dataSource);
+				Control.ReloadData();
 			}
 			else if (e.PropertyName == Xamarin.Forms.ListView.IsPullToRefreshEnabledProperty.PropertyName)
 				UpdatePullToRefreshEnabled();