Fix collection detaching at the wrong time in attribute()
Summary:
Found in FatCRM where changes to collection attributes were not stored
anymore.
Test Plan:
New unittest to ensure that we get the attribute from the
detached collection, not from the original one.
Reviewers: dvratil
Reviewed By: dvratil
Subscribers: kde-pim
Tags: KDE PIM
Differential Revision: https://phabricator.kde.org/D19741