The fix for "MDEV-17698 MEMORY engine performance regression"
previously fixed this problem.

- Adding the test for MDEV-17724
- Re-recording wrong results for tests:
  * engines/iuds/r/insert_number
  * engines/iuds/r/update_delete_number
  which started to fail since MDEV-17698

Also, backporting a part of:
  MDEV-11485 Split Item_func_between::val_int() into virtual methods in Type_handler
for easier merge to 10.3.

MDEV-11167: InnoDB: Warning: using a partial-field key prefix in search, results in assertion failure or "Can't find record" error

Fix ha_rnd_init() argument (we do not doing scan but use rnd_pos)

Background: Used encryption key_id is stored to encryption metadata
i.e. crypt_data that is stored on page 0 of the tablespace of the
table. crypt_data is created only if implicit encryption/not encryption
is requested i.e. ENCRYPTED=[YES|NO] table option is used
fil_create_new_single_table_tablespace on fil0fil.cc.

Later if encryption is enabled all tables that use default encryption
mode (i.e. no encryption table option is set) are encrypted with
default encryption key_id that is 1. See fil_crypt_start_encrypting_space on
fil0crypt.cc.

ha_innobase::check_table_options()
	If default encryption is used and encryption is disabled, you may
        not use nondefault encryption_key_id as it is not stored anywhere.

The relevant InnoDB/XtraDB fixes up to 5.6.42 had already
been applied to MariaDB in commit 30c3d6db.

Revert some changes that appeared in
the merge commit 87d852f1.

Problem affects INPLACE ALTER rename columns.

innobase_rename_column_try(): some strcmp() was replaced with my_strcasecmp(),
queries to update data dictionary was updated to not match column name case.

LOCK view WRITE shouldn't block FLUSH view.
So we set the view's mdl_request type to it's tables.

my_read fixed as in higher versions.
my_pread made as my_read aware of partial read of huge chunks of files
MY_FULL_IO enabled for file operations

followup for c32f7ed2

reset lex->many_values for LOAD DATA, as it's used for
auto-inc range size estimation.

 which did not always correctly simulated io-cache::end_of_file.
The error was caused by implicit cast to unsigned of an intemediate term
in a formula.

For index merge union[or sort union], the estimates are not taken into account while calculating the selectivity of
a condition. So instead of showing the estimates of the index merge union[or sort union], it shows estimates equal to
all the records of the table.
The fix for the issue is to include the selectivity of index merge
union[or sort union] while calculating the selectivity of a condition.

branch.

--gdb now accepts an argument, it will be passed to gdb as a command.
multiple commands can be separated by a (non-standard and not escapable)
delimiter - semicolon (;).

Old usage with a bare --gdb continues to work too, of course.

Cherry-picked c47c0ca5 5441bbd3 339b9055

We should clear trailing zeroes in frac part. Otherwise
that tail is growing quickly and forces unnecessary truncating of
arguments.