make test less evil

git-svn-id: https://svn.apache.org/repos/asf/lucene/dev/branches/branch_4x@1618129 13f79535-47bb-0310-9956-ffa450edef68
remove dead code

git-svn-id: https://svn.apache.org/repos/asf/lucene/dev/branches/branch_4x@1618131 13f79535-47bb-0310-9956-ffa450edef68
fix test bug: don't try to seek past number of ords

git-svn-id: https://svn.apache.org/repos/asf/lucene/dev/branches/branch_4x@1618135 13f79535-47bb-0310-9956-ffa450edef68
improve test reproducibility and try to use more terms dicts impls

git-svn-id: https://svn.apache.org/repos/asf/lucene/dev/branches/branch_4x@1618143 13f79535-47bb-0310-9956-ffa450edef68