DERBY-3155: Verify that columns needed for triggers are buffered up by MERGE statements, even when the MERGE statements do not mention those columns; commit derby-3155-46-aa-deferredDeletes.diff.

git-svn-id: https://svn.apache.org/repos/asf/db/derby/code/trunk@1578945 13f79535-47bb-0310-9956-ffa450edef68