/// <summary>
/// Clears a container of references.
/// </summary>
/// <param name="element">The container being cleared.</param>
/// <param name="item">The data item that the container represented.</param>
protected override void ClearContainerForItemOverride(DependencyObject element, object item)
{
DataGridColumnHeader header = element as DataGridColumnHeader;
base.ClearContainerForItemOverride(element, item);
if (header != null)
{
header.Tracker.StopTracking(ref _headerTrackingRoot);
header.ClearHeader();
}
}
