Add a missing DBUG_RETURN function test_if_number().

               INSTALLATION

When starting mysqld as an MS Windows NT service, it crashed 
with "Error 1067: The process terminated unexpectedly".

The problem is that thread local variables are not allocated
and initialized properly when started as a service. When the
server is started as a regular executable, the problem does
not occur.

Analysis showed that this is a regression after the patch for 
Bug#11765237/Bug#11763065.   Before, the thread local storage
was initialized by the call chain:
win_main->my_basic_init->my_thread_basic_global_init->
my_thread_init

When the my_init() structure was changed, this initialization
was moved from win_main to mysqld_main.   When started as
a service win_main is run in a separate thread, which does
not have mysqld_main in its call path, so my_thread_init
is never called for this thread.

Added a call to my_thread_init / my_thread_end in the service
handler function, which solves the problem.

fails when running with ps-protocol).

The problem was that when running in --ps-protocol mode mysqltest.cc
didn't close created prepared statements. So, the plugins could not be
unistalled because there was a prepared statement using them.

A fix is to add a dummy statement that forces mysqltest.cc to close
the last prepared statement (which uses a plugin-defined table).

This patch corrects the problem by fixing the definition and alterations
of the mysql.user table in the .sql files.

Also included are new result files for tests that examine the name 
column of the mysql.user table.

When a RPM test build in a non-release branch is done,
the $MYSQL_BINDIR variable ends in "/usr"
(rather than in "/usr/lib" as in a RPM release build),
this made test "file_contents" fail.

A branch for this case is added to the test.
The test result is unchanged.

Issue:
      SSL_CIPHER set to a specific CIPHER name was not getting picked up by SHOW STATUS Command.

Solution:
      If specific cipher name is specified, avoid overwriting of Cipher List with default Cipher names.

pre-locking list caused by triggers).

The thing is that CREATE TRIGGER / DROP TRIGGER may actually
change pre-locking list of (some) stored routines.

The SP-cache does not detect such changes. Thus if sp_head-instance
is cached in SP-cache, subsequent executions of the cached
sp_head will use inaccurate pre-locking list.

The patch is to invalidate SP-cache on CREATE TRIGGER / DROP TRIGGER.

improved the result file readability.

Before this fix, two performance schema unit tests crashed on windows.

The problem was a missing initialization to PFS_atomics,
which caused the crash only for platform not compiled with native atomics.

This fix adds the missing initialization in the unit tests.
No production code was changed, this is a unit test bug only.

MAP 'REPAIR TABLE' TO RECREATE +ANALYZE FOR ENGINES NOT
SUPPORTING NATIVE REPAIR

Executing 'mysqlcheck --check-upgrade --auto-repair ...' will first issue
'CHECK TABLE FOR UPGRADE' for all tables in the database in order to check if the
tables are compatible with the current version of MySQL. Any tables that are
found incompatible are then upgraded using 'REPAIR TABLE'.

The problem was that some engines (e.g. InnoDB) do not support 'REPAIR TABLE'.
This caused any such tables to be left incompatible. As a result such tables were
not properly fixed by the mysql_upgrade tool.

This patch fixes the problem by first changing 'CHECK TABLE FOR UPGRADE' to return
a different error message if the engine does not support REPAIR. Instead of
"Table upgrade required. Please do "REPAIR TABLE ..." it will report
"Table rebuild required. Please do "ALTER TABLE ... FORCE ..."

Second, the patch changes mysqlcheck to do 'ALTER TABLE ... FORCE' instead of
'REPAIR TABLE' in these cases.

This patch also fixes 'ALTER TABLE ... FORCE' to actually rebuild the table.
This change should be reflected in the documentation. Before this patch,
'ALTER TABLE ... FORCE' was unused (See Bug#11746162)

Test case added to mysqlcheck.test

              NON-PRIMARY UNIQUE INDEX USING INNODB

This patch adds the HA_INPLACE_ADD_UNIQUE_INDEX_NO_WRITE
capability flag to InnoDB, indicating that concurrent reads
can be allowed while non-primary unique indexes are created.

This is an follow-up to Bug #11751388 which enabled concurrent
reads when creating non-primary non-unique indexes.

Test case added to innodb_mysql_sync.test.

FLUSH TABLES under FLUSH TABLES <list> WITH READ LOCK leads 
to assert failure.

This assert was triggered if a statement tried up upgrade a metadata
lock with an active FLUSH TABLE <list> WITH READ LOCK. The assert 
checks that the connection already holds a global intention exclusive
metadata lock. However, FLUSH TABLE <list> WITH READ LOCK does not
acquire this lock in order to be compatible with FLUSH TABLES WITH
READ LOCK. Therefore any metadata lock upgrade caused the assert to
be triggered.

This patch fixes the problem by preventing metadata lock upgrade
if the connection has an active FLUSH TABLE <list> WITH READ LOCK.
ER_TABLE_NOT_LOCKED_FOR_WRITE will instead be reported to the client.

Test case added to flush.test.

  @ mysql-test/r/ctype_latin1.result
  @ mysql-test/r/ctype_utf8.result
  @ mysql-test/t/ctype_latin1.test
  @ mysql-test/t/ctype_utf8.test
  Adding tests

  @ sql/mysqld.h
  @ sql/item.cc
  @ sql/sql_parse.cc
  @ sql/sql_view.cc

  Refactoring (thanks to Guilhem for the idea):

  Item_string::print() was hard to understand because of the different
  QT_ constants: in "query_type==QT_x", QT_x is explicitely included
  but the other two QT_ are implicitely excluded. The combinations
  with '||' and '&&' make this even harder.
  - logic is now more "explicit" by changing QT_ constants to a bitmap of flags:
    QT_ORDINARY: no change,
    QT_IS -> QT_TO_SYSTEM_CHARSET | QT_WITHOUT_INTRODUCERS,
    QT_EXPLAIN -> QT_TO_SYSTEM_CHARSET
    (QT_EXPLAIN was introduced in the first version of the Bug#57341 patch)
  - Item_string::print() is rewritten using those flags

  Bugfix itself:

  When QT_TO_SYSTEM_CHARSET is used alone (with no QT_WITHOUT_INTRODUCERS),
  we print string literals as follows:

  - display introducers if they were in the original query
  - print ASCII characters as is
  - print non-ASCII characters using hex-escape
  Note: as "EXPLAIN" output is only for human readability purposes
  and does not need to be a pasrable SQL, so using hex-escape is Ok.
  ErrConvString class perfectly suites for hex escaping purposes.

               CLIENT CONFIGURATION.

At startup, MySQL server/client programs do not read
configuration file pointed by MYSQL_HOME environment
variable.

This happened as, this environment variable was
handled by a different variable (DEFAULT_HOME_ENV)
in the code, which was ne'er initialized.

Fixed by changing it to MYSQL_HOME.