[COMMITTERS] pgsql: Fix COPY's handling of transition tables with indexes.

Fix COPY's handling of transition tables with indexes.

Commit c46c0e5202e8cfe750c6629db7852fdb15d528f3 failed to pass the
TransitionCaptureState object to ExecARInsertTriggers() in the case
where it's using heap_multi_insert and there are indexes.  Repair.

Thomas Munro, from a report by David Fetter
Discussion: https://postgr.es/m/20170708084213.GA14720%40fetter.org

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/1add0b15f117769f619af12720bea2f73d4f7359

Modified Files
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src/backend/commands/copy.c            | 2 +-
src/test/regress/expected/triggers.out | 7 ++++++-
src/test/regress/sql/triggers.sql      | 7 +++++++
3 files changed, 14 insertions(+), 2 deletions(-)