Make the PreFilter annotation support filtering of an immutable list.

[Krijger]

I'm working on a web application where I have a service method

@PreFilter("@securityAccessRightsBean.doesHaveDeleteRights(filterObject)")
public List<String> removeObjects(List<String> objectIds) {
    // impl here
}

and a controller that handles special flow for single objects, result ing in the use of the java.lang utility method

Collections.singletonList(singleObjectId)

which eventually becomes the filterObject. However, that results in an UnsupportedOperationException, due to the filterObject being mutated. I vote to support filtering immutable lists (see that added unit test) with this pull request.

Note I only ran the core modules unit tests.

[Krijger]

Would anyone mind to have a look at this?

[Krijger]

Ping

[rwinch]

For those looking at this issue refer to the discussion on JIRA https://jira.springsource.org/browse/SEC-2488

[rwinch]

I had thought this was a duplicate, but somehow did not find it initially. Duplicate of SEC-2083 w/ PR #19 Please refer to those for tacking