PIG-4022: Fix tez e2e test SkewedJoin_6

git-svn-id: https://svn.apache.org/repos/asf/pig/trunk@1604234 13f79535-47bb-0310-9956-ffa450edef68
PIG-4020: Fix tez e2e tests MapPartialAgg_[2-4], StreamingPerformance_[6-7] (PIG-4020-2.patch)

git-svn-id: https://svn.apache.org/repos/asf/pig/trunk@1604237 13f79535-47bb-0310-9956-ffa450edef68
PIG-3975: Multiple Scalar reference calls leading to missing records (knoguchi via rohini)

git-svn-id: https://svn.apache.org/repos/asf/pig/trunk@1604284 13f79535-47bb-0310-9956-ffa450edef68