Re-fix user resource for public local sites.

2.0.x never had a proper fix for the user resource on public local sites, which
meant that rbt patch couldn't apply patches from non team-member users. This
change ports 2753b4b over to release-2.0.x.

Testing done: Ran unit tests.

Fixes bug 3582.
Merge branch 'release-2.0.x'