Fix timestamps in system.runtime.queries

[findepi]

Fixes #5462
Fixes #5464

[losipiuk]

I am a bit concerned about backward compatibility of this change. Not sure how commonly are those system schemas used by Presto users.

[findepi]

See
#4772
#4756
#4753
#4752
i guess system connector simply got missed during that effort, but @electrum @dain may know better.

[losipiuk]

fair

[losipiuk]

possible?

[findepi]

idk

[findepi]

fixed

[findepi]

AC

[losipiuk]

LGTM

[electrum]

We can do a sanity check to make the test failure reason obvious in case the system clock happens to be adjusted in between the calls

assertThat(timeAfter).isAfterOrEqualTo(timeBefore);

[findepi]

if the clock is adjusted, we still can fail, even if timeAfter >= timeBefore, so not sure how helpful it would be

[electrum]

We used the server time zone for JmxRecordSetProvider since that seems like the right thing to return. If the administrator chooses to run their server in a specific time zone, then that's probably what they want to see when looking at system tables. cc @dain

[findepi]

If we had an "instant" type, we would map to that. In the absence of "instant" type, we need to fill some zone, an we usually fill in UTC. eg
https://github.com/prestosql/presto/blob/fbd4ca7f6ca1326a077fd06cd33b687cbfe17cf2/presto-postgresql/src/main/java/io/prestosql/plugin/postgresql/PostgreSqlClient.java#L617
https://github.com/prestosql/presto/blob/91dbe5149ae593fc8f86d36a304f1f7e8dc9175c/presto-cassandra/src/main/java/io/prestosql/plugin/cassandra/CassandraRecordCursor.java#L109

[findepi]

Also, the problem with server zone is that it may be a political zone.
Presto engine has no problem representing (point-in-time, zone) pairs.
However, due to how they are formatted for the client, client can no longer distinguish values within
summer→winter DST change.

presto> SELECT
     ->     increment,
     ->     from_unixtime(base + increment * 3600, 'America/Los_Angeles')
     -> FROM (VALUES(1572766200)) t(base)
     -> CROSS JOIN UNNEST(sequence(0, 3)) u(increment);
     ->
 increment |                    _col1
-----------+---------------------------------------------
         0 | 2019-11-03 00:30:00.000 America/Los_Angeles
         1 | 2019-11-03 01:30:00.000 America/Los_Angeles
         2 | 2019-11-03 01:30:00.000 America/Los_Angeles
         3 | 2019-11-03 02:30:00.000 America/Los_Angeles
(4 rows)

[findepi]

#5488

[findepi]

CI failed -- #4936