row_purge_reset_trx_id(): Display a DBUG message about resetting the
DB_TRX_ID.

in JOIN::inject_best_splitting_cond

The value of SplM_opt_info::last_plan should be set to NULL
before any search for a splitting plan for a splittable
materialized table.

In case libaio is not found, and required,
remove variables HAVE_LIBAIO_H and HAVE_LIBAIO from cache, so that cmake
rerun after installation of libaio would succeed.

Conflicts:
	mysql-test/r/cte_nonrecursive.result
	mysql-test/suite/galera/r/galera_bf_abort.result
	mysql-test/suite/galera/r/galera_bf_abort_get_lock.result
	mysql-test/suite/galera/r/galera_bf_abort_sleep.result
	mysql-test/suite/galera/r/galera_enum.result
	mysql-test/suite/galera/r/galera_fk_conflict.result
	mysql-test/suite/galera/r/galera_insert_multi.result
	mysql-test/suite/galera/r/galera_many_indexes.result
	mysql-test/suite/galera/r/galera_mdl_race.result
	mysql-test/suite/galera/r/galera_nopk_bit.result
	mysql-test/suite/galera/r/galera_nopk_blob.result
	mysql-test/suite/galera/r/galera_nopk_large_varchar.result
	mysql-test/suite/galera/r/galera_nopk_unicode.result
	mysql-test/suite/galera/r/galera_pk_bigint_signed.result
	mysql-test/suite/galera/r/galera_pk_bigint_unsigned.result
	mysql-test/suite/galera/r/galera_serializable.result
	mysql-test/suite/galera/r/galera_toi_drop_database.result
	mysql-test/suite/galera/r/galera_toi_lock_exclusive.result
	mysql-test/suite/galera/r/galera_toi_truncate.result
	mysql-test/suite/galera/r/galera_unicode_pk.result
	mysql-test/suite/galera/r/galera_var_auto_inc_control_off.result
	mysql-test/suite/galera/r/galera_wsrep_log_conficts.result
	sql/field.cc
	sql/rpl_gtid.cc
	sql/share/errmsg-utf8.txt
	sql/sql_acl.cc
	sql/sql_parse.cc
	sql/sql_partition_admin.cc
	sql/sql_prepare.cc
	sql/sql_repl.cc
	sql/sql_table.cc
	sql/sql_yacc.yy

row_sel_get_clust_rec_for_mysql(): Look up the page from the
buffer pool, similar to how MySQL 5.7 does it.

debug_key_management
encrypt_and_grep
innodb_encryption

If real table count is different from what is expected by the test, it
just hangs on waiting to fulfill hardcoded number. And then exits with
**failed** after 10 minutes of wait: quite unfriendly and hard to
figure out what's going on.

Tests: detect table count for some encryption tests

Fix and enable some of the tests; some remain disabled.

The tests innodb_gis.rtree_old and innodb_gis.row_format
duplicated some versions of the test main.gis-rtree.
Instead of duplicating, source that test, in a new test
innodb_gis.innodb_gis_rtree.

Introduce innodb_row_format.combinations. Due to this,
ROW_FORMAT=COMPRESSED will not be covered in some tests
where it is covered in MySQL 5.7.

The function rtr_update_mbr_field_in_place() is generating
MLOG_REC_UPDATE_IN_PLACE or MLOG_COMP_REC_UPDATE_IN_PLACE records
on non-leaf pages, even though MLOG_WRITE_STRING would perfectly
suffice for updating a fixed-length data field.

btr_cur_parse_update_in_place(): If flags==7, the record may be
from rtr_update_mbr_field_in_place(), and we must check if the
page is a leaf page. Otherwise, assume that it is.

btr_cur_update_in_place(): Assert that the page is a leaf page.

While insert direction makes no sense for SPATIAL INDEX (R-tree),
the field is apparently being used (and basically garbage).
Relax the debug assertion that was added in MDEV-11369.

Other things, mainly to get
create_mysqld_error_find_printf_error tool to work:

- Added protection to not include mysqld_error.h twice
- Include "unireg.h" instead of "mysqld_error.h" in server
- Added protection if ER_XX messages are already defined
- Removed wrong calls to my_error(ER_OUTOFMEMORY) as
  my_malloc() and my_alloc will do this automatically
- Added missing %s to ER_DUP_QUERY_NAME
- Removed old and wrong calls to my_strerror() when using
  MY_ERROR_ON_RENAME (wrong merge)
- Fixed deadlock error message from Galera. Before the extra
  information given to ER_LOCK_DEADLOCK was missing because
  ER_LOCK_DEADLOCK doesn't provide any extra information.

I kept #ifdef mysqld_error_find_printf_error_used in sql_acl.h
to make it easy to do this kind of check again in the future

debug_key_management
encrypt_and_grep
innodb_encryption

If real table count is different from what is expected by the test, it
just hangs on waiting to fulfill hardcoded number. And then exits with
**failed** after 10 minutes of wait: quite unfriendly and hard to
figure out what's going on.

While the redo log format was changed in MariaDB 10.3.2 and 10.3.3
due to MDEV-12288 and MDEV-11369, it should be technically possible
to upgrade from a crashed MariaDB 10.2 instance.

On a related note, it should be possible for Mariabackup 10.3
to create a backup from a running MariaDB Server 10.2.

mlog_id_t: Put back the 10.2 specific redo log record types
MLOG_UNDO_INSERT, MLOG_UNDO_ERASE_END, MLOG_UNDO_INIT,
MLOG_UNDO_HDR_REUSE.

trx_undo_parse_add_undo_rec(): Parse or apply MLOG_UNDO_INSERT.

trx_undo_erase_page_end(): Apply MLOG_UNDO_ERASE_END.

trx_undo_parse_page_init(): Parse or apply MLOG_UNDO_INIT.

trx_undo_parse_page_header_reuse(): Parse or apply MLOG_UNDO_HDR_REUSE.

recv_log_recover_10_2(): Remove. Always parse the redo log from 10.2.

recv_find_max_checkpoint(), recv_recovery_from_checkpoint_start():
Always parse the redo log from MariaDB 10.2.

recv_parse_or_apply_log_rec_body(): Parse or apply
MLOG_UNDO_INSERT, MLOG_UNDO_ERASE_END, MLOG_UNDO_INIT.

srv_prepare_to_delete_redo_log_files(),
innobase_start_or_create_for_mysql(): Upgrade from a previous (supported)
redo log format.

trx_undo_page_report_rename(): Return a pointer to the start of the
undo log record, not to the start of the (not yet written) next free
record. The wrong return value would sometimes cause ROLLBACK to crash
in an assertion failure (trying to parse garbage from the free area at
the end of the insert_undo log page) if the TRX_UNDO_RENAME_TABLE record
was the very last thing that was written to the insert_undo log. This
would occasionally happen when an ALTER TABLE operation is rolled
back due to invalid FOREIGN KEY constraints in the innodb.innodb test.
In these tests, the error ER_ERROR_ON_RENAME (1025) would be returned
at the end of the ALGORITHM=COPY operation of ALTER TABLE.

trx_undo_page_report_modify(): For SPATIAL INDEX, keep logging
updated off-page columns twice, so that
the minimum bounding rectangle (MBR) will be logged.
Avoiding the redundant logging would require larger changes
to the undo log format.

row_build_index_entry_low(): Handle SPATIAL_UNKNOWN more robustly,
by refusing to purge the record from the spatial index.
We can get this code when processing old undo log from 10.2.10 or
10.2.11 (the releases affected by MDEV-14799, which was a regression
from MDEV-14051).

The InnoDB background tasks can modify tables while LOCK TABLES...WRITE
is in effect. The purge of InnoDB history always worked like this in
MariaDB, but in MySQL 5.7 it sometimes yields to LOCK TABLES.

Also, make gcol.innodb_virtual_index run the purge for an UPDATE
before DROP TABLE is executed.