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- Objects that don't have a UUID cannot cause linkintegrity-breaches.
This fixes http://dev.plone.org/plone/ticket/11904.
[WouterVH]
- Adjust tests to the changed URL used for the `folder_contents` view.
This refs http://dev.plone.org/plone/ticket/10122.
[gotcha]
- Add new tests to prove `isLinked` can now be used safely.
This refs http://dev.plone.org/plone/ticket/7784.
[gotcha]