/// <summary>
/// Searches for the specified object and returns the zero-based index of the last
/// occurrence within the range of elements in the list that contains the specified
/// number of elements and ends at the specified index.
/// </summary>
public static int LastIndexOf(SystemGenerics.List <T> list, T item, int index, int count)
{
(list as Mock)?.CheckDataRace(false);
return(list.LastIndexOf(item, index, count));
}
