pgsql: Flag index metapages as standard-format in xlog.c calls.

Flag index metapages as standard-format in xlog.c calls.

btree, hash, and bloom indexes all set up their metapages in standard
format (that is, with pd_lower and pd_upper correctly delimiting the
unused area); but they mostly didn't inform the xlog routines of this.
When calling log_newpage[_buffer], this is bad because it loses the
opportunity to compress unused data out of the WAL record. When
calling XLogRegisterBuffer, it's not such a performance problem because
all of these call sites also use REGBUF_WILL_INIT, preventing an FPI
image from being written. But it's still a good idea to provide the
flag when relevant, because that aids WAL consistency checking.

This completes the project of getting all the in-core index AMs to
handle their metapage WAL operations similarly.

Amit Kapila, reviewed by Michael Paquier

Discussion: https://postgr.es/m/0d273805-0e9e-ec1a-cb84-d4da400b8f85@lab.ntt.co.jp

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/4c11d2c559e76892156fd08d6a3cf5e1848a017f

Modified Files
--------------
contrib/bloom/blinsert.c | 2 +-
src/backend/access/hash/hashpage.c | 7 ++++---
src/backend/access/nbtree/nbtinsert.c | 4 ++--
src/backend/access/nbtree/nbtpage.c | 9 +++++----
src/backend/access/nbtree/nbtree.c | 2 +-
src/backend/access/nbtree/nbtxlog.c | 5 +++--
6 files changed, 16 insertions(+), 13 deletions(-)