of the previous user if it takes the username too.
otherwise it can never change to a passwordless account

- Avoid full inline of mark_trx_read_write() for many functions
- Avoid somewhat expensive tests for every write/update/delete row 

sql/handler.h:
  Adde ha_start_of_new_statement() to reset internal variables as part of the code in "open_table" that resets TABLE object for the new statement
  Faster mark_trx_read_write_part()
sql/sql_base.cc:
  Don't manipulate table->file internal structs directly

to close all system tables

sql/sql_class.cc:
  reset userstat_running after the data were colleced to prevent double accounting.
  don't assert for COM_QUERY, many more are possible.
  don't update_stats() here, it's too late, lex->sql_command may be already reset
sql/sql_parse.cc:
  update_stats() here, when the current arena is still valid

Add vcol test suite to `make dist`.

The cause of the problem is a bad merge MariaDB-5.1=>MariaDB-5.2.

Added the vcol suite to the list of the default suites run 
by mysql-test-run.pl.

2. don't copy st_mysql_plugin structure unnecessary (sizeof hasn't changed)

storage/myisam/mi_create.c:
  Don't set HA_OPTION_NULL_FIELDS if table is not using CHECKSUM as this makes the table incompatible with MySQL.

- Now DELETE IGNORE skips over rows with a foreign key constraints (as it was supposed to do)


mysql-test/r/foreign_key.result:
  Test case for Bug#44987 DELETE IGNORE and FK constraint
mysql-test/t/foreign_key.test:
  Test case for Bug#44987 DELETE IGNORE and FK constraint
sql/sql_delete.cc:
  Firx for Bug#44987 DELETE IGNORE and FK constraint
  Now DELETE IGNORE skips over rows with a foreign key constraints (as it was supposed to do)
  Bug fix inspired by: Moritz Mertinkat

Add some extra error output and code cleanup in an attempt to fix/debug
a rare random testsuite problem in check_warnings, where the exit code
from mysqltest is somehow corrupted inside mysql-test-run.pl.

include/my_global.h:
  Fix compiler warnings on some platforms.
mysql-test/lib/My/SafeProcess.pm:
  Move dereference of $? subprocess exit code closer to where it is generated,
  to make the code more robust and on the chance that this will fix the
  occasional problems in check_warnings we see in Buildbot.
mysql-test/mysql-test-run.pl:
  When check_warnings failed, also log the mysqld server for which it failed.
sql/sql_lex.cc:
  Fix compiler warning about possibly uninitialised value, by rewriting a for()
  loop that is always executed at least once into a do .. while() loop with an
  assert.
sql/table.cc:
  Fix compiler warning about uninitialised value.
storage/federatedx/ha_federatedx.cc:
  Fix uninitialised variable.
storage/maria/ma_delete.c:
  Fix compiler warning about uninitialised value.
storage/maria/ma_loghandler.c:
  Fix compiler warning about uninitialised value.
storage/myisam/ft_stopwords.c:
  Fix compiler warning.
storage/myisam/mi_write.c:
  Fix compiler warning about possibly uninitialised value, by rewriting a while()
  loop that is always executed at least once into a do .. while() loop with an
  assert.
storage/xtradb/btr/btr0cur.c:
  Fix compiler warning about possibly uninitialised value.
support-files/compiler_warnings.supp:
  Fix warning suppression to cover all cases in yassl.
vio/viossl.c:
  Fix compiler warning.

 - Adjust timing in test case, to avoid test failures caused by high load
   on machines and consequent race conditions in the test case.

 - Add another variant of Valgrind suppressions for memory leak in system
   libraries when unloading dynamic object files.


mysql-test/r/information_schema.result:
  Adjust timing to avoid test failures due to races.
mysql-test/t/information_schema.test:
  Adjust timing to avoid test failures due to races.
mysql-test/valgrind.supp:
  Add another variant of valgrind suppression for leak in system libs.

query:
- When subquery is located in ORDER BY, EXPLAIN will run as follows:
  select_describe() will run JOIN::prepare()/optimize() for the subquery;
  then at some point subselect_single_select_engine::prepare() will be called,
  which will create another join and run join->prepare().

  In mainline mysql this is not a problem because subquery's join will be 
  destroyed after the first call. 
  In MariaDB, it won't (table elimination needs to keep JOIN objects around
  for longer in order to know which tables were eliminated when constructing
  EXPLAIN EXTENDED warning).

  Fix the problem of memory leak by calling select_lex->cleanup() in 
  subselect_single_select_engine::prepare().

tmp_table_size can now be set to 0 (to disable in memory internal temp tables)
Improved speed for internal Maria temp tables:
- Don't use packed keys, except with long text fields.
- Don't copy key all accessed pages during key search.
Some new benchmark tests to sql-bench (for group by)

BUILD/compile-pentium64-gcov:
  Update script to use same pentium_config flags as other tests
BUILD/compile-pentium64-gprof:
  Update script to use same pentium_config flags as other tests
include/my_sys.h:
  Added count of my_sync calls
mysql-test/r/variables.result:
  tmp_table_size can now be set to 0
sql-bench/test-select.sh:
  Added some new test for GROUP BY on a not key field and group by with different order by
sql/mysqld.cc:
  Added count of my_sync calls
  tmp_table_size can now be set to 0 (to disable in memory internal temp tables)
sql/sql_select.cc:
  If tmp_table_size is 0, don't use in memory temp tables (good for benchmarking MyISAM/Maria temp tables)
  Don't pack keys for Maria tables;  The 8K page size makes packed keys too slow for temp tables.
storage/maria/ma_key_recover.h:
  Moved definition to maria_def.h
storage/maria/ma_page.c:
  Moved code used to simplify comparing of identical Maria tables to own function (page_cleanup())
  Fixed that one can read a page with a read lock.
storage/maria/ma_rkey.c:
  For not exact key reads, cache the page where we found key (to speed up future read-next/read-prev calls)
storage/maria/ma_search.c:
  Moved code to cache last key page to separate function.
  Instead of copying pages, only get a link to the page. This notable speeds up key searches on bigger tables.
storage/maria/ma_write.c:
  Added comment
storage/maria/maria_def.h:
  Moved page_cleanup() to separate function.

Bug#46949: memory leak with failed alter table to create partitions based on extract()

Bug#51830: Incorrect partition pruning on range partition (regression)

Fixed valgrind failure in select_describe(), read of uninitialized 
  Item_subselect::eliminated.

PBXT test file updates to reflect changes done in MySQL.

mysql-test/suite/pbxt/r/partition_error.result:
  Result file update following MySQL 5.1.44 changes.
mysql-test/suite/pbxt/r/partition_pruning.result:
  Result file update following MySQL 5.1.44 changes.
mysql-test/suite/pbxt/t/partition_error.test:
  Test file update following MySQL 5.1.44 changes.
sql/item_subselect.cc:
    Fixed valgrind failure in select_describe(), read of uninitialized 
    Item_subselect::eliminated: 
    - it turns out we can call select_describe() without having fixed 
      subquery items for child subselects. These are not the kind of subqueries
      that we could eliminate, so the fix is to ensure that 
      item_subselect->eliminated==FALSE even before fix_fields is called.
      Also added code to reset item_subselect->eliminated back to FALSE in
      Item::reset() call.
sql/item_subselect.h:
    Fixed valgrind failure in select_describe(), read of uninitialized 
    Item_subselect::eliminated: 
    - it turns out we can call select_describe() without having fixed 
      subquery items for child subselects. These are not the kind of subqueries
      that we could eliminate, so the fix is to ensure that 
      item_subselect->eliminated==FALSE even before fix_fields is called.
      Also added code to reset item_subselect->eliminated back to FALSE in
      Item::reset() call.
sql/sql_partition.cc:
  Fix Bug#51830: Revert part of the patch for Bug#49742, which caused the regression.
sql/table.cc:
  Fix Bug#46949: memory leak in failed ALTER TABLE with partitioning.

Save no-records constant tables in JOIN::const_table_map before we invoke
eliminate_tables(). Failure to do so caused crash when the same table was
marked as constant two times

mysql-test/r/table_elim.result:
  LPBUG#524025 Running RQG outer_join test leads to crash
  - Testcase
mysql-test/t/table_elim.test:
  LPBUG#524025 Running RQG outer_join test leads to crash
  - Testcase
sql/sql_select.cc:
  LPBUG#524025 Running RQG outer_join test leads to crash
  Save no-records constant tables in JOIN::const_table_map before we invoke eliminate_tables(). Failure to do so caused crash when the same table was marked as constant two times.

(Problem was missing time_zone setting)

- When analying multiple equalities, take into account that they 
  may not have a single table field that belongs to one of the tables
  that we're trying to eliminate (and they are not useful for table
  elimination in that case)

mysql-test/r/table_elim.result:
  LPBUG#523593: Running RQG optimizer_no_subquery crashes MariaDB
  - Testcase
mysql-test/t/table_elim.test:
  LPBUG#523593: Running RQG optimizer_no_subquery crashes MariaDB
  - Testcase

5 minutes on current machines. Tested on a Xeon machine and a new dual core laptop.

 - Changes to the banner text
 - Use older AC_PROG_LIBTOOL (Bug#51009)

scripts/mysql_install_db.sh
 - Changes to banner text

mysql-test/suite/maria/r/maria3.result:
  Updated test results
mysql-test/suite/maria/t/maria3.test:
  Don't show maria_used_for_temp_tables, as it's value is depending on configure options

mysql-test/suite/maria/r/group_commit.result:
  Test of gruoup commit.
mysql-test/suite/maria/r/maria3.result:
  The new variables added.
mysql-test/suite/maria/t/group_commit.test:
  Test of group commit.
randgen:
  Randon query generator tests.
randgen/conf:
  Random query generator tests.
randgen/conf/maria_group_commit.yy:
  Random query generator test for group commit.
storage/maria/ha_maria.cc:
  New variables and support procedures for group commit added.
storage/maria/ma_init.c:
  Correct shutdown of group commit service thread and group commit.
storage/maria/ma_loghandler.c:
  Group commit added.
  Initialization of variables for embeded server edded.
storage/maria/ma_loghandler.h:
  Group commit types and routines.

Now mysqld --help --verbose shows the value for thread-handling
Fixed also that mysqld --one-thread works as expected.

mysql-test/suite/parts/t/partition_repair_myisam-master.opt:
  Added missing file from last push
sql-bench/bench-init.pl.sh:
  Added options:
  --temporary-tables to test speed of temporary tables
sql-bench/server-cfg.sh:
  Added limit for number of temporary tables one can create
sql-bench/test-connect.sh:
  Skip test that doesn't work with temporary tables.
sql-bench/test-create.sh:
  Added limit for number of temporary tables one can create