Celerity map late update

Summary:
This change is probably needed after 892f527b9f6330a1131b564d2aef0b3f8e8aafa5.
At that time, the unit test was successfully completed probably because of a lack
of git rebase master.

Test Plan: The unit test PhabricatorCelerityTestCase::testCelerityMaps is not screaming.

Reviewers: O1 Blessed Committers, avivey

Reviewed By: O1 Blessed Committers, avivey

Subscribers: tobiaswiese, Matthew, Cigaryno

Differential Revision: https://we.phorge.it/D25553