This test needs at least 320M for tokudb-max-lock-memory.
Normally tokudb-max-lock-memory is auto-sized to be 1/16th
of the available RAM size, and many our test VMs have 4G of RAM.

Do not calculate selectivity of conditions for the tables of the information schema.

The problem reported as MDEV-5444.

- include metadata_lock_info plugin into debian packages
- ignore metadata_lock_info plugin in mysqld--help test
- let test suite run with built-in metadata_lock_info plugin

The fix for bug #27937 was incomplete: it did not handle correctly the queries
containing UNION with global ORDER BY in subselects.

(better to have an address in the output than ??:0)

(PLUGIN_VAR_MEMALLOC is 0x8000 and cannot be saved in a char as such)"

https://github.com/Tokutek/ft-engine/issues/153

don't reset interrupted_query after sending the KILL signal, otherwise
the client won't know it has to stop fetching and printing the data.

Removed unused_tables, find LRU object by timestamp instead.

- tc_acquire_table and tc_release_table do not access
  TABLE_SHARE::tdc.used_tables anymore
- in tc_acquire_table(): release LOCK_tdc after we relase LOCK_open
  (saves a few CPU cycles in critical section)
- in tc_release_table(): if we reached table cache threshold, evict
  to-be-released table without moving it to unused_tables. unused_tables
  must be empty at this point.

fix the element deleting logic for roles_mappings_hash

use generic restore_ptr_backup() approach

MDEV-4403 Attempting to use cassandra storage engine causes "service 'my_snprintf_service' interface version mismatch"

When a DSO is loaded we rewrite service pointers to point to the actual service structures.
But when a DSO is unloaded, we have to restore their original values, in case this DSO
wasn't removed from memory on dlclose() and is later loaded again.

* comments from WL#5602 in sql_acl.cc
* rename global memroots in sql_acl.cc
* remove the second empty lex string constant

  Remove unused code (that should not have been merged)
  Add protocol extension (that should have been merged)
  Fix bugs (see pack.c)

Patially merge WL#5917, to understand v2 row events

a memory leak in save_index() first seen in the test case for mdev-5382.

When marking used columns the function find_field_in_table_ref() erroneously
called the walk method for the real item behind a view/derived table field
with the second parameter set to TRUE.
This erroneous code was introduced in 2006. 

Correct processing of view/derived with no tables added.

"Conditional jump or move depends on uninitialised"
in Item_time_typecast::get_date.

Adding "null_value" into the debug assert condition.

modified:
  mysql-test/r/func_time.result
  mysql-test/t/func_time.test
  sql-common/my_time.c
  sql/item_func.h
  sql/item_timefunc.cc
  sql/mysql_priv.h
  sql/time.cc

fix a copy-paste error, introduced in role refactoring