Update CHANGELOG-EE.md for 8.16.4-ee

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CHANGELOG-EE.md

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+## 8.16.4 (2017-02-02)
+
+- Disable all merge acceptance buttons pending MR approval.
+
 ## 8.16.3 (2017-01-27)
 
 - Fix sidekiq cluster mishandling of queue names. !1117

changelogs/unreleased-ee/1595-merge-when-pipeline-succeeds-visible-if-approvals-are-pending.yml

----
-title: Disable all merge acceptance buttons pending MR approval.
-merge_request: !1101
-author: