fix(mc): closes #2519, fix err message/suggest workaround for test-merges
fix(mc): closes #2519, fix err message/suggest workaround for test-merges

AdamHillier/activity-stream,Mardak/activity-stream,mozilla/activity-stream,mozilla/activity-stream,Mardak/activity-stream,sarracini/activity-stream,Mardak/activity-stream,JaredKerim-Mozilla/activity-stream,JaredKerim-Mozilla/activity-stream,rlr/activity-streams,rlr/activity-streams,mozilla/activity-streams,sarracini/activity-stream,mozilla/activity-stream,mozilla/activity-streams,mozilla/activity-stream,sarracini/activity-stream,rlr/activity-streams,AdamHillier/activity-stream,JaredKerim-Mozilla/activity-stream,Mardak/activity-stream,sarracini/activity-stream,JaredKerim-Mozilla/activity-stream,AdamHillier/activity-stream,AdamHillier/activity-stream,rlr/activity-streams