Variant#5 of the patch:
- take creation date from the .frm file, like InnoDB does
- Update_time is in-memory only (like in InnoDB).

Temporarily revert the patch

doubles in scientific notation with a big integer part.

MDEV-19516 mysql_secure_installation doesn't set password_last_changed while setting password for root

Redo changes reverted in commit
8f46e383, this time without build
issues in wsrep-lib.

This is the only 10.4-specific fix. The remaining known issues
will be fixed by merging commit bef843b9
from 10.3.

Don't assume that passwords (and other conv replies) are zero-terminated.
If they are, though, strndup() down below will take care of that.

This reverts commit 2b5f4b3e
due to build failures.

Update wsrep-lib, and adapt to wsrep-lib interface changes.

Ignore warning.

Changes to be committed:
	modified:   mysql-test/suite/galera_sr/disabled.def
	modified:   mysql-test/suite/galera_sr/r/GCF-561.result
	modified:   mysql-test/suite/galera_sr/r/galera_sr_ddl_master.result
	modified:   mysql-test/suite/galera_sr/r/galera_sr_kill_query.result
	modified:   mysql-test/suite/galera_sr/r/galera_sr_shutdown_slave.result
	new file:   mysql-test/suite/galera_sr/suite.pm
	modified:   mysql-test/suite/galera_sr/t/GCF-561.test
	modified:   mysql-test/suite/galera_sr/t/galera_sr_ddl_master.test
	modified:   mysql-test/suite/galera_sr/t/galera_sr_kill_query.test
	modified:   mysql-test/suite/galera_sr/t/galera_sr_shutdown_slave.test

Test should die if innodb_compression_algorithm=3 doesn't exists

Fixes MDEV-18067, MDEV-18068 and MDEV-18069

The problem was that FLUSH TABLES table_name combined with UNLOCK TABLES
calls MDL_context::set_transaction_duration_for_all_locks(), which
changed backup_locks from MDL_EXPLICT to MDL_TRANSACTION.

Fixed by ensuring that set_transaction_duration_for_all_locks() doesn't
touch BACKUP locks.

added forgotem WITH option to spacial case with INTO

Instrumenting parallel slave worker thread with wsrep replication hooks.
Added mtr test for testing parallel slave support.
The test is based on the test attached in MDEV-6860 jira tracker.

rec_init_offsets(): Relax the assertion that was added in
commit 01f45bec
to catch ROW_FORMAT=REDUNDANT records that have fewer fields
than expected.

This assertion would fail when accessing the records of the
built-in InnoDB table SYS_INDEXES. The column MERGE_THRESHOLD
had been effectively instantly added in MariaDB Server 10.2
(and MySQL 5.7), but is_instant() does not hold for that index.
Relax the assertion, so that it will not fail in this case.

MDEV-20813 Assertion failure in buf_flush_init_for_writing() for innodb_immediate_scrub_data_uncompressed=ON

The assertion that was added in
commit c0c003be
to augment the fix of MDEV-20805 turns out to be invalid when
innodb_immediate_scrub_data_uncompressed is enabled.
In this mode, fsp_init_file_page() will be invoked on data pages
that have been freed, causing writes of almost-all-zero pages.

btr_page_free(): Adjust the comment.

buf_flush_init_for_writing(): Disable the assertion with a note
that it should be re-enabled in MDEV-15528.

When the mysqld_multi script passes the --defaults-group-suffix
option to mysqld, it must remove the initial substring with the
group name ("mysqld") from option value, because otherwise substring
"mysqld" will be added to the group name and then the group name
will contain the word "mysqld" twice, which is wrong, because
mysqld itself adds the suffix received to the group name.

When the mysqld_multi script passes the --defaults-group-suffix
option to mysqld, it must remove the initial substring with the
group name ("mysqld") from option value, because otherwise substring
"mysqld" will be added to the group name and then the group name
will contain the word "mysqld" twice, which is wrong, because
mysqld itself adds the suffix received to the group name.

When the mysqld_multi script passes the --defaults-group-suffix
option to mysqld, it must remove the initial substring with the
group name ("mysqld") from option value, because otherwise substring
"mysqld" will be added to the group name and then the group name
will contain the word "mysqld" twice, which is wrong, because
mysqld itself adds the suffix received to the group name.

When the mysqld_multi script passes the --defaults-group-suffix
option to mysqld, it must remove the initial substring with the
group name ("mysqld") from option value, because otherwise substring
"mysqld" will be added to the group name and then the group name
will contain the word "mysqld" twice, which is wrong, because
mysqld itself adds the suffix received to the group name.

This is another follow-up fix to
commit b393e2cb
which turned out to be still broken.

Replace the C++11 keyword 'constexpr' with #define.

debug_sync_t::str: Remove the zero-length array.
Replace sync->str with reinterpret_cast<char*>(&sync[1]).

During IMPORT TABLESPACE, we do invoke
buf_flush_init_for_writing() with block==NULL and newest_lsn!=0.

Remove unused variables and type mismatch that was introduced
in commit b393e2cb

Also, fix a typo in the documentation of the parameter, and
update the test.

buf_flush_init_for_writing(): Assert that FIL_PAGE_TYPE is set
except when creating a new data file with a dummy first page.

buf_dblwr_create(): Ensure that FIL_PAGE_TYPE on all pages
will be initialized. Reset buf_dblwr_being_created at the end.

In the function recv_parse_or_apply_log_rec_body() there are debug checks
for validating the state of the page when redo log records are being
applied. Most notably, FIL_PAGE_TYPE should be set before anything else
is being written to the page.

ibuf_add_free_page(): Set FIL_PAGE_TYPE before performing any other changes.

Apply the correct pattern for debug instrumentation:

SET @save_dbug=@@debug_dbug;
SET debug_dbug='+d,...';
...
SET debug_dbug=@save_dbug;

Numerous tests use statements of the form

SET debug_dbug='-d,...';

which will inadvertently enable all DBUG tracing output,
causing unnecessary waste of resources.