pgsql: Further second thoughts about idle_session_timeout patch.

Further second thoughts about idle_session_timeout patch.

On reflection, the order of operations in PostgresMain() is wrong.
These timeouts ought to be shut down before, not after, we do the
post-command-read CHECK_FOR_INTERRUPTS, to guarantee that any
timeout error will be detected there rather than at some ill-defined
later point (possibly after having wasted a lot of work).

This is really an error in the original idle_in_transaction_timeout
patch, so back-patch to 9.6 where that was introduced.

Branch
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REL9_6_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/388ec04f14366d5df0c9b7958c5d9c09d4327f3a

Modified Files
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src/backend/tcop/postgres.c | 22 ++++++++++++----------
1 file changed, 12 insertions(+), 10 deletions(-)