Add an [identity constraints] property of the schema component, which
contains all the identity constraint components, just as the [type
definitions] property contains all the type definition components.

The problem identified here was clarified by Henry
(http://lists.w3.org/Archives/Member/w3c-xml-schema-ig/2002Nov/0124.html).

This item was mentioned in the meeting of 2003-09-18
(http://www.w3.org/XML/Group/2003/09/xml-schema-ftf-minutes.html).

This item was closed in the meeting of 2003-11-04
(http://www.w3.org/XML/Group/2003/11/xml-schema-ftf-minutes.html), on
the theory that the issue had been classified as an erratum for XML
Schema 1.0 (R-105
(http://www.w3.org/2001/05/xmlschema-rec-comments.html#pfiSchemaComponent))
and did not need to be taken care of as part of 1.1.  Cf. also RQ-133.

In any case, the problem has been fixed in XML Schema 1.1 (beginning
with the working draft of July 2004), so this can be closed with a
status of RESOLVED / FIXED.