Preallocate locks on THD mem_root to avoid expensive malloc.

Let some atomic counters use relaxed memory order.

timestamp has a lower granularity on windows so it needs
more time to change.

        The GEOMETRY field metadata is stored in the FRM file.
        SRID for a spatial column now can be stored, it was added to the CREATE TABLE syntax,
        so the AddGeometryData() stored procedure is now possible. Script adding the required Add/DropGeometryColumn sp-s added.

length/dec/charset are still in LEX, because they're also used
for CAST and dynamic columns.

also
1. fix "MDEV-7041 COLLATION(CAST('a' AS CHAR BINARY)) returns a wrong result"
2. allow BINARY modifier in stored function RETURN clause
3. allow "COLLATION without CHARSET" in SP/SF (parameters, RETURN, DECLARE)
4. print correct variable name in error messages for stored routine parameters

If persistent trim is not used some OS require that we write full page.

thd_specifics service

when many plugins are active, all must approve the password

don't do it in the parser, one should not make run-time
decisions (like, checking thd->variables.old_passwords variable)
during parsing.

* indeed, "username IDENTIFIED BY PASSWORD hash" is the same
  as "username IDENTIFIED VIA mysql_native_password USING hash"
* LEX_USER::password can now be used for plain-text passwords

REQUIRE and MAX_QUERIES_PER_HOUR can not possibly apply to a role

* remove no-op check_password_policy() and references to it
* add 'static' to functions that need it
* remove unused function check_acl_user()

  username IDENTIFIED BY PASSWORD xxx
  username IDENTIFIED VIA mysql_native_password USING xxx
  etc

also check for valid strlen(xxx)

* test for opt->name being non-NULL *before* dereferencing it
* remove unused argument in cleanup_variables()
* simplify

Rows_log_event::write_row - don't optimize DELETE+INSERT
into UPDATE if RBR triggers are used

revert the patch for "out parameters in prepare"