Fixes the following bugs:

- Bug #33349: possible race condition revolving around data dictionary and repartitioning
  Introduce retry/sleep logic as a workaround for a transient bug
  where ::open fails for partitioned tables randomly if we are using
  one file per table.

- Bug #34053: normal users can enable innodb_monitor logging
  In CREATE TABLE and DROP TABLE check whether the table in question is one
  of the magic innodb_monitor tables and whether the user has enough rights
  to mess with it before doing anything else.

- Bug #22868: 'Thread thrashing' with > 50 concurrent conns under an upd-intensive workloadw
- Bug #29560: InnoDB >= 5.0.30 hangs on adaptive hash rw-lock 'waiting for an X-lock'
  This is a combination of changes that forward port the scalability fix applied to 5.0
  through r1001.
  It reverts changes r149 and r122 (these were 5.1 specific changes made in lieu of
  scalability fix of 5.0)
  Then it applies r1001 to 5.0 which is the original scalability fix.
  Finally it applies r2082 which fixes an issue with the original fix.

- Bug #30930: Add auxiliary function to retrieve THD::thread_id
  Add thd_get_thread_id() function.  Also make check_global_access() function
  visible to InnoDB under INNODB_COMPATIBILITY_HOOKS #define.