Fixed ASTERIXDB-1249 and ASTERIXDB-1250: self index-nested-loop join correctly identifies the outer and the inner branch.

The first dataset becomes the outer branch.
The second dataset becomes the inner branch.
The optimizer for index-nested-loop join now only try to use an index from the inner branch.

Change-Id: I0d4291197c2bcfbcdcde998c5952af41960c4ad7
Reviewed-on: https://asterix-gerrit.ics.uci.edu/576
Reviewed-by: Yingyi Bu <buyingyi@gmail.com>
Tested-by: Jenkins <jenkins@fulliautomatix.ics.uci.edu>
diff --git a/asterix-app/src/test/resources/optimizerts/queries/inverted-index-join/ngram-edit-distance-contains.aql b/asterix-app/src/test/resources/optimizerts/queries/inverted-index-join/ngram-edit-distance-contains.aql
index 4178083..7d9c5d2 100644
--- a/asterix-app/src/test/resources/optimizerts/queries/inverted-index-join/ngram-edit-distance-contains.aql
+++ b/asterix-app/src/test/resources/optimizerts/queries/inverted-index-join/ngram-edit-distance-contains.aql
@@ -50,7 +50,7 @@
 
 write output to asterix_nc1:"rttest/inverted-index-join_ngram-edit-distance-contains.adm";
 
-for $a in dataset('DBLP')
 for $b in dataset('CSX')
+for $a in dataset('DBLP')
 where edit-distance-contains($a.authors, $b.authors, 3)[0] and $a.id < $b.id
 return {"arec": $a, "brec": $b }