Dynamic column functions

Functions DATABASE() and USER().

INET4/INET6 functions

- INT result functions
- CAST variants: COLLATE, BINARY, CONVERT(..USING)

UDF

Numeric functions with string input

Boolean predicates

XML functions

Adding tests for cast, bit functions, string functions.

GIS functions

Testing non-ASCII string literals.

- real functions
- temporal functions
- hybrid functions

MDEV-10134 Add full support for DEFAULT

- Added support for using tables with MySQL 5.7 virtual fields,
  including MySQL 5.7 syntax
- Better error messages also for old cases
- CREATE ... SELECT now also updates timestamp columns
- Blob can now have default values
- Added new system variable "check_constraint_checks", to turn of
  CHECK constraint checking if needed.
- Removed some engine independent tests in suite vcol to only test myisam
- Moved some tests from 'include' to 't'. Should some day be done for all tests.
- FRM version increased to 11 if one uses virtual fields or constraints
- Changed to use a bitmap to check if a field has got a value, instead of
  setting HAS_EXPLICIT_VALUE bit in field flags
- Expressions can now be up to 65K in total
- Ensure we are not refering to uninitialized fields when handling virtual fields or defaults
- Changed check_vcol_func_processor() to return a bitmap of used types
- Had to change some functions that calculated cached value in fix_fields to do
  this in val() or getdate() instead.
- store_now_in_TIME() now takes a THD argument
- fill_record() now updates default values
- Add a lookahead for NOT NULL, to be able to handle DEFAULT 1+1 NOT NULL
- Automatically generate a name for constraints that doesn't have a name
- Added support for ALTER TABLE DROP CONSTRAINT
- Ensure that partition functions register virtual fields used. This fixes
  some bugs when using virtual fields in a partitioning function

use Item->neg to convert generate negative Item_num's
instead of Item_func_neg(Item_num).

Based on the following commit:

  Author: Monty <monty@mariadb.org>
  Date:   Mon May 30 22:44:00 2016 +0300

    Make negative number their own token
    The negation (-) operator will call Item->neg() one underlying numeric constants
    and remove itself (like the NOT() function does today for other NOT functions.

    This simplifies things
    - -1 is not anymore an expression but a basic_const_item
      - improves optimizer
      - DEFAULT -1 doesn't need special handling anymore
      - When we add DEFAULT expressions, -1 will be treated exactly like 1
    - printing of items doesn't anymore put braces around all negative numbers

    Other things fixed:
    - Fixed that longlong converted to decimal's has a more appropriate size
    - Fixed that "-0.0" read into a decimal is interpreted as 0.0

Fixed some test for future when DELETE will not trigger row based replication

Print default values for BLOB's.
This is a part commit for automatic changes to make the real commit smaller.
All changes here are related to that we now print DEFAULT NULL for blob and
text fields, like we do for all other fields.

of bugs easier (MDEV-8919, MDEV-10304, MDEV-10305, MDEV-10307)

- Adding Item::push_note_converted_to_negative_complement() and
  Item::push_note_converted_to_positive_complement()
- Adding virtual methods Item::val_int_signed_typecast() and
  Item::val_int_unsigned_typecast()
- Moving COLUMN_GET() related code from
  Item_func_signed::val_int() and Item_func_unsigned::val_int() to
  Item_dyncol_get::val_int_signed_typecast() and
  Item_dyncol_get::val_int_unsigned_typecast()
- Moving Item_func_signed::val_int_from_str() to Item::val_int_from_str()
  and changing it to get the value from "this" instead of args[0].

The patch does not change behaviour. It's only to simplify fixing of the
mentioned bugs. It will also simplify switching the CAST related code to
use the type handler infrastructure easier (soon).

Result file in engines/funcs test suite needs to be updated accordingly

Fixed ccfilter to detect errors where the column is included in the error message

MDEV-10219 rpl.rpl_parallel_temptable failed in buildbot: Assertion `!table || !table->in_use || table->in_use == _current_thd()' failed

Problem was that table->in_use was not properly set when dropping a temporary for the slave.

Decimals with float, double and decimal now works the following way:

- DECIMAL_NOT_SPECIFIED is used when declaring DECIMALS without a firm number
  of decimals.  It's only used in asserts and my_decimal_int_part.
- FLOATING_POINT_DECIMALS (31) is used to mark that a FLOAT or DOUBLE
  was defined without decimals. This is regarded as a floating point value.
- Max decimals allowed for FLOAT and DOUBLE is FLOATING_POINT_DECIMALS-1
- Clients assumes that float and double with decimals >= NOT_FIXED_DEC are
  floating point values (no decimals)
- In the .frm decimals=FLOATING_POINT_DECIMALS are used to define
  floating point for float and double (31, like before)

To ensure compatibility with old clients we do:

- When storing float and double, we change NOT_FIXED_DEC to
  FLOATING_POINT_DECIMALS.
- When creating fields from .frm we change for float and double
  FLOATING_POINT_DEC to NOT_FIXED_DEC
- When sending definition for a float/decimal field without decimals
  to the client as part of a result set we convert NOT_FIXED_DEC to
  FLOATING_POINT_DECIMALS.
- variance() and std() has changed to limit the decimals to
  FLOATING_POINT_DECIMALS -1 to not get the double converted floating point.
  (This was to preserve compatiblity)
- FLOAT and DOUBLE still have 30 as max number of decimals.

Bugs fixed:

variance() printed more decimals than we support for double values.

New behaviour:
- Strings now have 38 decimals instead of 30 when converted to decimal
- CREATE ... SELECT with a decimal with > 30 decimals will create a column
  with a smaller range than before as we are trying to preserve the number of
  decimals.


Other changes
- We are now using the obsolete bit FIELDFLAG_LEFT_FULLSCREEN to specify
  decimals > 31
- NOT_FIXED_DEC is now declared in one place
- For clients, NOT_FIXED_DEC is always 31 (to ensure compatibility).
  On the server NOT_FIXED_DEC is DECIMAL_NOT_SPECIFIED (39)
- AUTO_SEC_PART_DIGITS is taken from DECIMAL_NOT_SPECIFIED
- DOUBLE conversion functions are now using DECIMAL_NOT_SPECIFIED instead of
  NOT_FIXED_DEC

Added my_global.h to PerconeFT to avoid "error <my_config.h> MUST be included first"

Some rdiff files in storage_engine test suite need to be updated accordingly

General spell fixing in comments and strings

MDEV-10098 main.create_delayed fails with ps-protocol: assertion `global_status_var.global_memory_used >= 0' failed

Remove the assert. We cannot verify that
global_memory_used value is valid (>=0)
because some of updates are cached in individual THD's
(e.g. THD1 can have +300 cached, while the other THD2
can have -300 cached. If the second THD exists before
the first one, global_memory_used will be -300
temporarily).

Instead add the assert just before the exit, when all
THDs been already destroyed.

always update global_status_var.global_memory_used
through update_global_memory_status()

Since a query can now refer to the same temporary table
multiple times, find_dup_table()/find_table_in_list()
have been updated to also consider this new possibility.

Temporary table being created by outer statement
should not be visible to inner statement. And if
inner statement creates a table with same name.
The whole statement should fail with
ER_TABLE_EXISTS_ERROR.

Implemented by temporarily de-linking the TABLE_SHARE
being created by outer statement so that it remains
hidden to the inner statement.

mysqld maintains a list of TABLE objects for all temporary
tables created within a session in THD. Here each table is
represented by a TABLE object.

A query referencing a particular temporary table for more
than once, however, failed with ER_CANT_REOPEN_TABLE error
because a TABLE_SHARE was allocate together with the TABLE,
so temporary tables always had only one TABLE per TABLE_SHARE.

This patch lift this restriction by separating TABLE and
TABLE_SHARE objects and storing TABLE_SHAREs for temporary
tables in a list in THD, and TABLEs in a list within their
respective TABLE_SHAREs.

Add generic temporary table related tests.

- unused TABLE_SHARE::deleting and TABLE_LIST::deleting flags were removed
- kill_delayed_threads_for_table() and intern_close_table() are now private
  methods of table cache
- removed free_share flag of closefrm(): it was never used for temporary
  tables and was rarely useful for regular tables

make INFORMATION_SCHEMA.PROCESSLIST.MEMORY_USED bigint

MDEV-10180 main.events_restart fails on valgrind builder: void THD::inc_thread_count(): Assertion `!abort_loop' failed.

remove an overly strong assert

Replaced hard-coded cache line size.

Changes based on Daniel Black's work.