[wsrp-wsia] [change request #165] Semantics of no userProfile vs nouserProfile data

[Rich Thompson <richt2@us.ibm.com>]

Document: Spec
Section: 6.1.19 UserContext Type
Page/Line: 39/22
Requested by: Andre Kramer

Old text: [insert]
Proposed text: A Consumer that is sharing a Portlet among users MUST NOT 
supply a value for the userProfile field. A Consumer that is not sharing a 
Portlet MAY omit all userProfile fields if no user information is 
available or requested but MUST supply a userProfile field.

Reasoning:
A producer MAY then use the fact that UserProfile is or is not nil, for 
example,  in deciding whether content rendered is cacheable for the given 
user context (i.e. the perUser scope can then be for a particular end user 
or a group of users identified by a UserContextKey) or for all users 
(other userContextKeys then the one that content was rendered for).

Better than an extra boolean: UserContext.isSharedContext?

[need to then make the element nillable in wsdl or add a boolean element]