PIG-3458: ScalarExpression lost with multiquery optimization (knoguchi)


git-svn-id: https://svn.apache.org/repos/asf/pig/branches/branch-0.12@1526257 13f79535-47bb-0310-9956-ffa450edef68
PIG-2417 - fix for compilation failure due to unmappable character for encoding UTF8 (jeremykarn via rohini)

git-svn-id: https://svn.apache.org/repos/asf/pig/branches/branch-0.12@1526288 13f79535-47bb-0310-9956-ffa450edef68