Allocates and initializes a LocalContextItem structure. It also allocates dataSize user data. User data can be accesseed via LocalItemData function. This is the only way to allocate such a item, since the item contains private fields. Of course programmers should assume NOTHING about this private fields.
INPUTS
type, id
Longword identifications values.
ident
Longword identifier for class of item.
dataSize
Size of a user data area that will be allocated by this funcyion.