Statement timeout logging

Hi,

When a statement is cancelled due to it running for long enough for
statement_timeout to take effect, it logs a message:

ERROR: canceling statement due to statement timeout

However, it doesn't log what the timeout was at the time of the
cancellation. This may be set in postgresql.conf, the database, or on
the role, but unless log_line_prefix is set to show the database name
and the user name, there's no reliable way of finding out what context
the configuration applied from. Setting log_duration won't help
either because that only logs the duration of completed queries.

Should we output the statement_timeout value when a query is cancelled?

--
Thom