fix filter backlog content when not logged in

Change-Id: I31be06c26017d2c8ff2e553fd3b709a155320cf2
Merge commit 'refs/changes/14/1814/1' of ssh://gerrit.tuleap.net:29418/tuleap into tuleap-stable-master

* ssh://gerrit.tuleap.net:29418/tuleap:
  fix filter backlog content when not logged in

Change-Id: I52e181fc2260224256b3339d22f1a02e645b9179
Tuleap 6.9.99.38

Change-Id: Ia3491ea77f4ca9324ace8f09533ac36173c6b677