array_diff throw notices in 5.4+ and seems unreliable for recursive array

Change-Id: I850f8bdcc475768413b0c585d66e326a4a4363ba
Merge commit 'refs/changes/42/2942/2' of ssh://gerrit.tuleap.net:29418/tuleap into stable

* ssh://gerrit.tuleap.net:29418/tuleap:
  array_diff throw notices in 5.4+ and seems unreliable for recursive array
This is Tuleap 7.5.99.65

Change-Id: Idfa203d56800b2687f7e2dd261ca1e933dfe5fb8