public class CustomGridView: RadGridView
{
    private static readonly PropertyInfo internalColumnsProp = typeof(GridViewDataControl).GetProperty("InternalColumns", BindingFlags.Instance | BindingFlags.NonPublic);
    private static MethodInfo invalidateColumnsMethod;

    protected override Size MeasureOverride(Size availableSize)
    {
        if (EnableRowVirtualization && !double.IsInfinity(availableSize.Height))
        {
            var internalColumns = internalColumnsProp.GetValue(this);
            if (invalidateColumnsMethod == null)
            {
                invalidateColumnsMethod = internalColumns.GetType().GetMethod("InvalidateColumnWidthsCalculation", BindingFlags.Instance | BindingFlags.NonPublic);                     
            }

            invalidateColumnsMethod.Invoke(internalColumns, null);
        }
        return base.MeasureOverride(availableSize);
    }