Re:pg_stat_statements and "IN" conditions

Hello!

Unfortunately the patch needs another rebase due to the recent split of guc.c
(0a20ff54f5e66158930d5328f89f087d4e9ab400)

I'm reviewing a patch on top of a previous commit and noticed a failed test:

#   Failed test 'no parameters missing from postgresql.conf.sample'
#   at t/003_check_guc.pl line 82.
#          got: '1'
#     expected: '0'
# Looks like you failed 1 test of 3.
t/003_check_guc.pl .............. 

The new option has not been added to the postgresql.conf.sample

PS: I would also like to have such a feature. It's hard to increase pg_stat_statements.max or lose some entries just
becausesome ORM sends requests with a different number of parameters.
 

regards, Sergei