Add the functionality that was removed in WL#6044. However, this is a compelete
rewrite of SHOW ... MUTEX infrastructure inside InnoDB. The RW-Locks tracking
however was not changed in any substantial way. Except that some useless debug
counters were removed and the waits are now enabled/reset/disabled using the
Monitor infrastructure.

In the old SHOW ... MUTEX For each mutex pointer and rw-lock pointer we were
doing a search through all the buffer pool chunks to check if the pointer was
contained within to identify if it was a page mutex/rw-lock or not. For large
buffer pools this is unacceptable. To avoid these expensive scans, I've added
a LATCH_ID to identify each mutex and rw-lock. Removed the cfile_name and
cline from the mutex definition and moved them to a separate lookup table.
This information is only used when there is a problem and is very rare but
under normal operation they take up sizeof(void*) + sizeof(uint16_t) space,
the sizeof(uint16_t) actually occupies 8 bytes due to the alignment. The size
of the mutex was therefore 72 bytes. It has now been reduced to:

We don't track the create file and line number for the block mutexes. There
are just too many of them and they are all created in the same file(buf0buf.cc)
and on the same line number, you can grep the code to figure that out.

  gdb) p sizeof(ib_mutex_t)
      $1 = 48

For rw_lock_t, add a is_block_lock flag. This flag is set in buf0buf.cc where
the block lock is created.

Removed UNIV_SYNC_DEBUG. UNIV_DEBUG will by default do sync order checking.
Add read-only debug config variable: --innodb-sync-debug (default: true).
Potential use case is to run the latch ordering checks in the weekly tests
if the overhead is too much for daily tests.

Added dynamic enable/disable/reset of mutex/rw statistic gathering using
the existing monitor infrastructure

    SET GLOBAL innodb_monitor_enable="latch";
    SET GLOBAL innodb_monitor_reset="latch";
    SET GLOBAL innodb_monitor_disable="latch";

Added additonal information to the SHOW ... MUTEX OUTPUT

mysql> show engine innodb mutex;
+--------+-------------------------+------------------------------------------+
| Type   | Name                    | Status                                   |
+--------+-------------------------+------------------------------------------+
| InnoDB | TRX_SYS                 | spins=3371806,waits=44790,calls=800875   |
...
| InnoDB | rwlock: log0log.cc:784  | waits=3                                  |
+--------+-------------------------+------------------------------------------+

The "Name" columns will now display the mutex name and not the filename:line
format which was very build specific. For RW-LOCKS we will stick with the old
format.

Fixed several bugs in the SyncDebug checks that were introduced in WL#6044.

Moved the low level OS mutex to a separate class with a separate interface.
We can't track these because they are implemented outside of InnoDB.

Remove UNIV_DEBUG_FILE_ACCESSES, fold into UNIV_DEBUG

Approved by Jimmy Yang and Bin Su rb#9037