Innodb monitor could cause a server crash because of invalid access to a
shared variable in a concurrent environment.
                  
This patch adds a guard to protect against crashes but not against
inconsistent values because of performance reasons.

where it was forgotten to remove them.

refining the regression test to avoid explicit innodb engine in create.

Prevent this by modifying CFLAGS and CXXFLAGS.

Upmerge from 5.0, modified according to the different spec file structure.

Prevent this by modifying CFLAGS and CXXFLAGS.

Problem 1: BUG#36625: rpl_redirect doesn't do anything useful. It tests an
obsolete feature that was never fully implemented.
Fix 1: Remove rpl_redirect.
Problem 2: rpl_innodb_bug28430 and rpl_flushlog_loop are disabled despite the
bugs for which they were disabled have been fixed.
Fix 2: Re-enable rpl_innodb_bug28430 and rpl_flushlog_loop.

The convert_constant_item function converts a constant to integer using
field for condition like 'field = a_constant'. In some cases the
convert_constant_item is called for a subquery when outer select is already
being executed, so convert_constant_item saves field's value to prevent its
corruption. For EXPLAIN and at the prepare phase field's value isn't
initialized yet, thus when convert_constant_item tries to restore saved
value it fails assertion.

Now the convert_constant_item doesn't save/restore field's value if it's
haven't been read yet. Outer constant values are always saved.

order by

Problem was that the first index read was unordered,
and the next was ordered, resulting in use of
uninitialized data.

Solution was to use the correct variable to see if
the 'next' call should be ordered or not.

  Bug#39848 events_bugs fails sporadically on pushbuild
            (missing rows in table event_log)
     Details: Reimplement the subtest for BUG 28924
              - check if the number of rows within the table
                event_log changes but don't print rows
                because the number varies depending on
                load on testing box
              - shift DROP USER befor DROP EVENT
                = Subtest fits again to old bug
              - remove no more needed comments + variables
  Bug#39863 events_bugs fails sporadically on pushbuild 
            (extra processes in I_S.PROCESSLIST)
     Details: Abort with appropriate message to the protocol if
              release_lock() does not has the intended effect.
              This cannot prevent problems caused by the probably
              buggy release_lock() but it reveals if we had a
              problem in this area.
  Bug#39978 main.events_bugs does not clean up
     Detail: Restore global.event_scheduler = ON at end of test
  Bug#39569 events_bugs fails sporadically on pushbuild
            (should have failed with errno 1539)
     Detail: Set $wait_timeout to 4 instead of 2
- Fix two instabilities (result sets pulled from processlist in
  subtest for bug 16407) which were found during tests with high
  parallel I/O load
- Minor improvements of formatting
  Details:
  - Add comments
  - Remove tabs and trailing blanks
  - Add line breaks for better readability

updating two test results.

correct text describing the --plugin-load option to mysqld