1. Removing data type specific constants from enum_item_param_state,
   adding SHORT_DATA_VALUE instead.
2. Replacing tests for Item_param::state for the removed constants to
   tests for Type_handler::cmp_type() against {INT|REAL|TIME|DECIAML}_RESULT.
   Deriving Item_param::PValue from Type_handler_hybrid_field_type,
   to store the data type handler of the current value of the parameter.

3. Moving Item_param::decimal_value and Item_param::str_value_ptr
   to Item_param::PValue. Adding Item_param::PValue::m_string
   and changing Item_param to use it to store string values,
   instead of Item::str_value. The intent is to replace Item_param::value
   to a st_value based implementation in the future, to avoid duplicate code.
   Adding a sub-class Item::PValue_simple, to implement
   Item_param::PValue::swap() easier.
   Remaming Item_basic_value::fix_charset_and_length_from_str_value()
   to fix_charset_and_length() and adding the "CHARSET_INFO" pointer
   parameter, instead of getting it directly from item->str_value.charset().
   Changing Item_param to pass value.m_string.charset() instead
   of str_value.charset().
   Adding a String argument to the overloaded
   fix_charset_and_length_from_str_value() and changing Item_param
   to pass value.m_string instead of str_value.

4. Replacing the case in Item_param::save_in_field() to a call
   for Type_handler::Item_save_in_field().

5. Adding new methods into Item_param::PValue:
   val_real(), val_int(), val_decimal(), val_str().
   Changing the corresponding Item_param methods
   to use these new Item_param::PValue methods
   internally. Adding a helper method
   Item_param::can_return_value() and removing
   duplicate code in Item_param::val_xxx().

6. Removing value.set_handler() from Item_param::set_conversion()
   and Type_handler_xxx::Item_param_set_from_value().
   It's now done inside Item_param::set_param_func(),
   Item_param::set_value() and Item_param::set_limit_clause_param().

7. Changing Type_handler_int_result::Item_param_set_from_value()
   to set max_length using attr->max_length instead of
   MY_INT64_NUM_DECIMAL_DIGITS, to preserve the data type
   of the assigned expression more precisely.

8. Adding Type_handler_hybrid_field_type::swap(),
   using it in Item_param::PValue::swap().

9. Moving the data-type specific code from
   Item_param::query_val_str(), Item_param::eq(),
   Item_param::clone_item() to
   Item_param::value_query_type_str(),
   Item_param::value_eq(), Item_param::value_clone_item(),
   to split the "state" dependent code and
   the data type dependent code.
   Later we'll split the data type related code further
   and add new methods in Type_handler. This will be done
   after we replace Item_param::PValue to st_value.

10. Adding asserts into set_int(), set_double(), set_decimal(),
   set_time(), set_str(), set_longdata() to make sure that
   the value set to Item_param corresponds to the previously
   set data type handler.

11. Adding tests into t/ps.test and suite/binlog/t/binlog_stm_ps.test,
   to cover Item_param::print() and Item_param::append_for_log()
   for LIMIT clause parameters.
   Note, the patch does not change the behavior covered by the new
   tests. Adding for better code coverage.

12. Adding tests for more precise integer data type in queries like this:
    EXECUTE IMMEDIATE
     'CREATE OR REPLACE TABLE t1 AS SELECT 999999999 AS a,? AS b'
      USING 999999999;
    The explicit integer literal and the same integer literal
    passed as a PS parameter now produce columns of the same data type.
    Re-recording old results in ps.result, gis.result, func_hybrid_type.result
    accordingly.

- sql_prepare.cc: Moving functions set_param_xxx() as
  methods to Item_param

- Replacing a pointer to a function Item_param::set_param_func
  to Type_handler based implementation:
  Item_param::value now derives from Type_handler_hybrid_field_type.
  Adding new virtual methods Type_handler::Item_param_setup_conversion()
  and Type_handler::Item_param_set_param_func()

- Moving declaration of some Item_param members  from "public:" to "private:"
  (CONVERSION_INFO, value, decimal_value)

- Adding a new method Item_param::set_limit_clause_param(),
  to share duplicate code, as well as to encapsulate
  Item_param::value.

- Adding Item_param::setup_conversion_string() and
  Item_param::setup_conversion_blob() to share
  the code for binding from a client value
  (mysql_stmt_bind_param), and for binding from
  an expression (Item).

- Removing two different functions set_param_str_or_null()
  and set_param_str(). Adding a common method Item_param::set_param_str().
  Item_param::m_empty_string_is_null, used by Item_param::set_param_str().

- Removing the call for setup_one_conversion_function() from
  insert_params_from_actual_params_with_log(). It's not needed,
  because the call for ps_param->save_in_param() makes sure
  to initialized all data type dependent members properly,
  by calling setup_conversion_string() from
  Type_handler_string_result::Item_param_set_from_value()
  and by calling setup_conversion_blob() from
  Type_handler_blob_common::Item_param_set_from_value()

- Cleanup: removing multiplication to MY_CHARSET_BIN_MB_MAXLEN
  in a few places. It's 1 anyway, and will never change.

A cleanup for MDEV-12846 sql_mode=ORACLE: using Oracle-style placeholders in direct query execution makes the server crash

Fixing a test failure in "mtr --ps compat/oracle.ps" caused by "SELECT ?"
returning different errors:
- CR_PARAMS_NOT_BOUND in prepared execution
- ER_PARSE_ERROR in direct execution
Disabling PS protocol for this test chunk.

dict_stats_exec_sql(): Refuse the operation if shutdown has been
initiated.

The real fix would be to update the persistent statistics as part
of the data dictionary transactions. To do this, we should move the
storage of InnoDB persistent statistics to the InnoDB data files,
and maybe also remove the InnoDB data dictionary.

Item_param::set_value() did not set Item::collation and
Item_param::str_value_ptr.str_charset properly. So both
metadata and data for OUT parameters were sent in a wrong
way to the client.

This patch removes the old implementation of Item_param::set_value()
and rewrites it using Type_handler::Item_param_set_from_value(),
so now setting IN and OUT parameters share the a lot of code.

1. Item_param::set_str() now:
  - accepts two additional parameters fromcs, tocs
  - sets str_value_ptr, to make sure it's always in sync with str_value,
    even without Item_param::convert_str_value()
  - does collation.set(tocs, DERIVATION_COERCIBLE),
    to make sure that DTCollation is valid even without
    Item_param::convert_str_value()

2. Item_param::set_value(), which is used to set OUT parameters,
   now reuses Type_handler::Item_param_set_from_value().

3. Cleanup: moving Item_param::str_value_ptr to private,
   as it's not needed outside.

4. Cleanup: adding a new virtual method
   Settable_routine_parameter::get_item_param()
   and using it a few new DBUG_ASSERTs, where
   Item_param cannot appear.

After this change:
1. Assigning of IN parameters works as before:
a. Item_param::set_str() is called and sets the value as a binary string
b. The original value is sent to the query used for binary/general logging
c. Item_param::convert_str_value() converts the value from the client
   character set to the connection character set

2. Assigning of OUT parameters works in the new way:
a. Item_param::set_str() and sets the value
   using the source Item's collation, so both Item::collation
   and Item_param::str_value_ptr.str_charset are properly set.
b. Protocol_binary::send_out_parameters() sends the
   value to the client correctly:
   - Protocol::send_result_set_metadata() uses Item::collation.collation
     (which is now properly set), to detect if conversion is needed,
     and sends a correct collation ID.
   - Protocol::send_result_set_row() calls Type_handler::Item_send_str(),
     which uses Item_param::str_value_ptr.str_charset
     (which is now properly set) to actually perform the conversion.

Also, MDEV-14317 When ALTER TABLE is aborted, do not write garbage pages to data files

As pointed out by Shaohua Wang, the merge of MDEV-13328 from
MariaDB 10.1 (based on MySQL 5.6) to 10.2 (based on 5.7)
was performed incorrectly.

Let us always pass a non-NULL FlushObserver* when writing
to data files is desired.

FlushObserver::is_partial_flush(): Check if this is a bulk-load
(partial flush of the tablespace).

FlushObserver::is_interrupted(): Check for interrupt status.

buf_LRU_flush_or_remove_pages(): Instead of trx_t*, take
FlushObserver* as a parameter.

buf_flush_or_remove_pages(): Remove the parameters flush, trx.
If observer!=NULL, write out the data pages. Use the new predicate
observer->is_partial() to distinguish a partial tablespace flush
(after bulk-loading) from a full tablespace flush (export).
Return a bool (whether all pages were removed from the flush_list).

buf_flush_dirty_pages(): Remove the parameter trx.

MDEV-14435 Different UNSIGNED flag of out user variable for YEAR parameter for direct vs prepared CALL

is set to true, as it should.

Copy and modify original io_win.h header file to a different location
(as we cannot patch anything in submodule). Make sure modified header is
used.

        Result unescaping added.

This is caused by following change:

commit 95d29c99f01882ffcc2259f62b3163f9b0e80c75
Author: Marko Mäkelä <marko.makela@oracle.com>
Date:   Tue Nov 27 11:12:13 2012 +0200

    Bug#15920445 INNODB REPORTS ER_DUP_KEY BEFORE CREATE UNIQUE INDEX COMPLETED

    There is a phase during online secondary index creation where the index has
    been internally completed inside InnoDB, but does not 'officially' exist yet.
    We used to report ER_DUP_KEY in these situations, like this:

    ERROR 23000: Can't write; duplicate key in table 't1'

    What we should do is to let the 'offending' operation complete, but report an
    error to the
    ALTER TABLE t1 ADD UNIQUE KEY (c2):

    ERROR HY000: Index c2 is corrupted
    (This misleading error message should be fixed separately:
    Bug#15920713 CREATE UNIQUE INDEX REPORTS ER_INDEX_CORRUPT INSTEAD OF DUPLICATE)

    row_ins_sec_index_entry_low(): flag the index corrupted instead of
    reporting a duplicate, in case the index has not been published yet.

    rb:1614 approved by Jimmy Yang

Problem is that after we have found duplicate key on primary key
we continue to get necessary gap locks in secondary indexes to
block concurrent transactions from inserting the searched records.
However, search from unique index used in foreign key constraint
could return DB_NO_REFERENCED_ROW if INSERT .. ON DUPLICATE KEY UPDATE
does not contain value for foreign key column. In this case
we should return the original DB_DUPLICATE_KEY error instead
of DB_NO_REFERENCED_ROW.

Consider as a example following:

create table child(a int not null primary key,
b int not null,
c int,
unique key (b),
foreign key (b) references
parent (id)) engine=innodb;

insert into child values (1,1,2);

insert into child(a) values (1) on duplicate key update c = 3;

Now primary key value 1 naturally causes duplicate key error that will be
stored on node->duplicate. If there was no duplicate key error, we should
return the actual no referenced row error. As value for column b used in
both unique key and foreign key is not provided, server uses 0 as a
search value. This is naturally, not found leading to DB_NO_REFERENCED_ROW.
But, we should update the row with primay key value 1 anyway as
requested by on duplicate key update clause.

Fix of nondebuging version issue

This problem was earlier fixed in bb-10.2-ext.
Adding tests only.

The patch for MDEV-11146 fixed this problem earlier.
Only adding tests from the report.

MDEV-12846 sql_mode=ORACLE: using Oracle-style placeholders in direct query execution makes the server crash

than the query itself

ACL checks were not properly supported for tables used in CTE
specifications. This patch fixes the problem.

        Check for the empty 'coordinates' array.

Reinit internal state of select_unit before using to correctly run it after first time.

MDEV-13723: Server crashes in ha_heap::find_unique_row or Assertion `0' failed in st_select_lex_unit::optimize with INTERSECT

With INTERSECT/EXCEPT fact that subquery item of IN/ALL/ANY was not assigned value does not mean that temporary table used for calculating unit is empty (records could be deleted).

        Character bigger than 0x60 wasn't handled properly
        inside a numeric constant.