pgsql: Use FLEXIBLE_ARRAY_MEMBER for HeapTupleHeaderData.t_bits[].

Use FLEXIBLE_ARRAY_MEMBER for HeapTupleHeaderData.t_bits[].

This requires changing quite a few places that were depending on
sizeof(HeapTupleHeaderData), but it seems for the best.

Michael Paquier, some adjustments by me

Branch
------
master

Details
-------
http://git.postgresql.org/pg/commitdiff/e1a11d93111ff3fba7a91f3f2ac0b0aca16909a8

Modified Files
--------------
contrib/file_fdw/file_fdw.c                     |    2 +-
contrib/pageinspect/heapfuncs.c                 |   17 +++----
contrib/postgres_fdw/postgres_fdw.c             |    2 +-
src/backend/access/common/heaptuple.c           |    2 +-
src/backend/access/heap/heapam.c                |   56 +++++++++++------------
src/backend/access/heap/tuptoaster.c            |   10 ++--
src/backend/catalog/toasting.c                  |    2 +-
src/backend/executor/nodeHash.c                 |    2 +-
src/backend/optimizer/path/costsize.c           |    6 +--
src/backend/optimizer/plan/planner.c            |    4 +-
src/backend/optimizer/plan/subselect.c          |    8 ++--
src/backend/optimizer/prep/prepunion.c          |    2 +-
src/backend/optimizer/util/plancat.c            |    2 +-
src/backend/replication/logical/decode.c        |   30 ++++++------
src/backend/replication/logical/reorderbuffer.c |   26 +++++------
src/backend/utils/adt/trigfuncs.c               |    6 +--
src/include/access/htup_details.h               |   12 +++--
src/include/access/tuptoaster.h                 |    2 +-
src/include/replication/reorderbuffer.h         |   10 ++--
19 files changed, 102 insertions(+), 99 deletions(-)