- MDEV-5689 ExtractValue(xml, 'substring(/x,/y)') crashes
- MDEV-5709 ExtractValue() with XPath variable references returns wrong result.

Description:

1. The main problem was that that nodeset_func->fix_fields() was
called in Item_func_xml_extractvalue::val_str() and
Item_func_xml_update::val_str(), which led in some cases to
execution of the XPath engine *before* having a parsed XML value.
Moved to Item_xml_str_func::fix_fields().

2. Cleanup: added a new method Item_xml_str_func::fix_fields() and moved
most of the code from Item_xml_str_func::fix_length_and_dec()
to Item_xml_str_func::fix_fields(), to follow the usual Item layout.

3. Cleanup: a parsed XML value is useless without the raw XML value
it was built from.

Previously the parsed and the raw values where stored in separate String
instances. It was hard to follow how they are synchronized.
Added a helper class XML which contains both parsed and raw values.
Makes things easier to read and modify.

4. MDEV-5709: const_item() could incorrectly return a "true"
result when XPath expression contains users/SP variable references.
Now nodeset_func->const_item() is also taken into account to
catch such cases.

5. Minor code enhancements.

A huge number in the "day" part of an interval made the code to return
a negative date erroneously. Adding a test to return an error on a too
large "day" value.

After constant table row substitution the where condition may be converted
to always true. The function calculate_cond_selectivity_for_table() should
take into account this possibility.

Due to how gap locks work, two transactions could group commit together on the
master, but get lock conflicts and then deadlock due to different thread
scheduling order on slave.

For now, remove these deadlocks by running the parallel slave in READ
COMMITTED mode. And let InnoDB/XtraDB allow statement-based binlogging for the
parallel slave in READ COMMITTED.

We are also investigating a different solution long-term, which is based on
relaxing the gap locks only between the transactions running in parallel for
one slave, but not against possibly external transactions.

When a transaction fails in parallel replication, it should signal the error
to any following transactions doing wait_for_prior_commit() on it. But the
code for this was incorrect, and would not correctly remember a prior error
when sending the signal. This caused corruption when slave stopped due to an
error.

Fix by remembering the error code when we first get an error, and passing the
saved error code to wakeup_subsequent_commits().

Thanks to nanyi607rao who reported this bug on
maria-developers@lists.launchpad.net and analysed the root cause.

- Forgot to update one .result file.

Analysis: XtraDB merge regression, at the end of mutex_spin_wait before goto mutex_loop
there is missing  

if (prio_mutex) { 
	os_atomic_decrement_ulint(&prio_mutex->high_priority_waiters, 1); 
}

Hence we get unbalanced waiter count.

Thanks to Laurynas Biveinis for finding this.

- Save range key before making field->pos_in_interval() call (like we do for non-equality ranges)

Let TABLE_SHARE::tdc.free_tables, TABLE_SHARE::tdc.all_tables,
TABLE_SHARE::tdc.flushed and corresponding invariants be protected by
per-share TABLE_SHARE::tdc.LOCK_table_share instead of global LOCK_open.

Now if CREATE OR REPLACE fails but we have deleted a table already, we will generate a DROP TABLE in the binary log.
This fixes this issue.

In addition, for a failing CREATE OR REPLACE TABLE ... SELECT we don't generate a log of all the inserted rows, only the DROP TABLE.

I added code for not logging DROP TEMPORARY TABLE for tables where the CREATE TABLE was not logged. This code will be activated in 10.1
by removing the code protected by DONT_LOG_DROP_OF_TEMPORARY_TABLES.





mysql-test/suite/rpl/r/create_or_replace_mix.result:
  More test cases
mysql-test/suite/rpl/r/create_or_replace_row.result:
  More test cases
mysql-test/suite/rpl/r/create_or_replace_statement.result:
  More test cases
mysql-test/suite/rpl/t/create_or_replace.inc:
  More test cases
sql/log.cc:
  Added binlog_reset_cache() to clear the binary log.
sql/log.h:
  Added prototype
sql/sql_insert.cc:
  If CREATE OR REPLACE TABLE ... SELECT fails:
  - Don't log anything if nothing changed
  - If table was deleted, log a DROP TABLE.
  Remember if we table creation of temporary tables was logged.
sql/sql_table.cc:
  Added log_drop_table()
  Remember if we table creation of temporary tables was logged.
  If CREATE OR REPLACE TABLE ... SELECT fails and a table was deleted, log a DROP TABLE.
sql/sql_table.h:
  Added prototype
sql/sql_truncate.cc:
  Remember if we table creation of temporary tables was logged.
sql/table.h:
  Added table_creation_was_logged

- Part#2: call HA_EXTRA_FLUSH for the correct handler object, and call it after every change
  (ha_write_row, ha_update_row, ha_delete_row).

mysql-test/r/create_or_replace2.result:
  Added test case
mysql-test/t/create_or_replace.test:
  Fixed comment
mysql-test/t/create_or_replace2.test:
  Added test case
sql/sql_base.cc:
  Safety fix:
  Don't let threads with query_id=0 free temporary tables as this may free temporary tables not in use.
  This is mostly the case for the slave io threads, as most other threads has thd->query_id != 0.
sql/sql_table.cc:
  Added comment.
  Ignore kill when opening temporary table for CREATE ... LIKE.
  This fixed the original isue

- Do like sp.cc does with mysql.proc table: call HA_EXTRA_FLUSH after we've modified
  a statistical table.

Corrected cost estimates when a join buffer is used and the optimizer is requested
to use condition selectivities.

Analysis: This was merge error on file fil0fil.cc. fil_system mutex was taken twice because of this.

Fix: Remove unnecessary mutex_enter and fixed the issue with slow posix_fallocate usage.

- If an UPDATE 1) modifies the key it is using, and 2) has ORDER BY ... LIMIT
  which matches the key it is using,  Then we should use "Using buffer", not
  "Using filesort". 

- Adopt MySQL's fix: don't run index_merge optimizer if the table statistics 
  reports that the table has 0 rows.

MDEV-5819: MySQL Bug #13500371 63704: CONVERSION OF '1.' TO A NUMBER GIVES ERROR 1265 (WARN_DATA_TRUNCATED)

Fix by MySQL ported

Automatic merge, except for server_audit.cc that had to be modified slightly
Changes to xtradb and innobase where ignored was these made no sence for 10.0

Fixed max_length of dynamic columns json/create/add functions.

mysql-test/r/create_or_replace.result:
  Added test of releasing of metadata locks
mysql-test/t/create_or_replace.test:
  Added test of releasing of metadata locks
sql/handler.h:
  Added marker if table was deleted as part of CREATE OR REPLACE
sql/sql_base.cc:
  Added Locked_tables_list::unlock_locked_table()
sql/sql_class.h:
  New prototypes
sql/sql_insert.cc:
  Unlock metadata locks for deleted table in case of error. Also do unlock tables if this was the only locked table.
sql/sql_table.cc:
  Unlock metadata locks for deleted table in case of error. Also do unlock tables if this was the only locked table.

Remove memory warnings if mysql client aborts early
Changed copyright for clients

client/mysql.cc:
  Free memory if get_options fails, so that we don't get warnings from safemalloc
include/welcome_copyright_notice.h:
  Added SkySQL to client copyrights
mysql-test/valgrind.supp:
  Added suppressions for memory leaks from dlopen() for OpenSUSE 12.3
storage/oqgraph/mysql-test/oqgraph/regression_mdev5744.result:
  Suppress warning
storage/oqgraph/mysql-test/oqgraph/regression_mdev5744.test:
  Suppress warning

meaning of the count, and to remove the alpha warning.

MDEV-5804: If same GTID is received on multiple master connections in multi-source replication, the event is double-executed causing corruption or replication failure

Some fixes, mainly to make it work in non-parallel replication mode also
(--slave-parallel-threads=0).

Patch should be fairly complete now.

extra/replace.c:
  Removed compiler warning
sql/unireg.cc:
  Removed compiler warning
storage/maria/ma_blockrec.c:
  Removed compiler warning
storage/maria/ma_dynrec.c:
  Fixed compiler failure
storage/maria/ma_unique.c:
  Removed compiler warning
storage/myisam/mi_check.c:
  Removed compiler warning
storage/myisam/mi_checksum.c:
  Removed compiler warning