innodb.innodb_stats_drop_locked fail and
innodb.innodb_stats_fetch_nonexistent fails in buildbot on Windows

Analysis: Problem is that innodb_stats_create_on_corrupted
test renames mysql.innodb.index_stats and all the rest
are dependend on this table.

Fix: After rename back to original, restart mysqld to
make sure that table is correct.

Analysis: Test case uses Linux specific error codes.

Fix: Can't run test case with Windows currently because requires
to inject error to system.

  Records can get to the different place in the log when multiple thread
    are logged. So the delay added to let the record be saved on the same
    place.

            server

This is an addition to original patch. Added full memory barrier to ensure
proper StoreLoad order between waiters and lock_word on PPC64.

Use traditional statistics estimation by default (innodb-stats-traditional=true).
There could be performance regression for customers if there is a lot of
open table operations.

* adjust viossl.c to take account the new code
  (SSL_get_error is used now, cannot simply remap it)
* remove unnecessary version check
* update the test to 10.0

This came with the upgrade from yassl 2.3.0 to 2.3.4 -
ssl tests started to hang on Windows. Comparing and removing changes
I've got to this:

 void input_buffer::set_current(uint i) 
 {
-    if (i)
-        check(i - 1, size_); 
-    current_ = i; 
+    if (error_ == 0 && i && check(i - 1, size_) == 0)
+        current_ = i;
+    else
+        error_ = -1;
 }

in 2.3.0 i==0 was only used to avoid the check, in 2.3.4 it's an error.
but there are places in the code that do set_current(0) and others that
do, like, { before=get_current(); ...; set_current(before); } - and the
initial value of current_ is 0.

So, I suspect that set_current(0) should not be an error, but it should
only skip the check().

innodb_stats_sample_pages

Analysis: If you set the number of analyzed pages 
to very low number compared to actual pages on 
that table/index it randomly pics those pages 
(default 8 pages), this leads to fact that query 
after analyze table returns different results. If 
the index tree is small, smaller than 10 * 
n_sample_pages + total_external_size, then the 
estimate is ok. For bigger index trees it is 
common that we do not see any borders between 
key values in the few pages we pick. But still 
there may be n_sample_pages different key values, 
or even more. And it just tries to 
approximate to n_sample_pages (8).

Fix: (1) Introduced new dynamic configuration variable
innodb_stats_sample_traditional  that retains
the current design. Default false.

(2) If traditional sample is not used we use
n_sample_pages = max(min(srv_stats_sample_pages,
                         index->stat_index_size),
                     log2(index->stat_index_size)*
                          srv_stats_sample_pages);

(3) Introduced new dynamic configuration variable
stat_modified_counter (default = 0) if set
sets lower bound for row updates when statistics is re-estimated.

If user has provided upper bound for how many rows needs to be updated
before we calculate new statistics we use minimum of provided value
and 1/16 of table every 16th round. If no upper bound is provided
(srv_stats_modified_counter = 0, default) then calculate new statistics
if 1 / 16 of table has been modified
since the last time a statistics batch was run.
We calculate statistics at most every 16th round, since we may have
a counter table which is very small and updated very often.
@param t table
@return true if the table has changed too much and stats need to be
recalculated
*/
#define DICT_TABLE_CHANGED_TOO_MUCH(t) \
	((ib_int64_t) (t)->stat_modified_counter > (srv_stats_modified_counter ? \
	ut_min(srv_stats_modified_counter, (16 + (t)->stat_n_rows / 16)) : \
		16 + (t)->stat_n_rows / 16))

followup:
* explicitly disable SSLv2 and SSLv3, keep other protocols enabled
* fix a compiler warning
* rename the test and combinations to avoid confusion

vio/viossl.c:
  fix a compiler warning

When the optimizer considers an option to use Loose Scan, it should 
still consider UNIQUE keys (Previously, MDEV-4120 disabled loose scan
for all kinds of unique indexes. That was wrong)

However, we should not use Loose Scan when trying to satisfy 
 "SELECT DISTINCT col1, col2, .. colN"
when using an index defined as UNIQU(col1, col2, ... colN).

The bug was that full memory barrier was missing in the code that ensures that
a waiter on an InnoDB mutex will not go to sleep unless it is guaranteed to be
woken up again by another thread currently holding the mutex. This made
possible a race where a thread could get stuck waiting for a mutex that is in
fact no longer locked. If that thread was also holding other critical locks,
this could stall the entire server. There is an error monitor thread than can
break the stall, it runs about once per second. But if the error monitor
thread itself got stuck or was not running, then the entire server could hang
infinitely.

This was introduced on i386/amd64 platforms in 5.5.40 and 10.0.13 by an
incorrect patch that tried to fix the similar problem for PowerPC.

This commit reverts the incorrect PowerPC patch, and instead implements a fix
for PowerPC that does not change i386/amd64 behaviour, making PowerPC work
similarly to i386/amd64.

The problem is that the binlog position is updated before 
Executed_log_entries and Slave_SQL_State. So, it's possible to hit 
the moment when MASTER_POS_WAIT (and hence sync_with_master) already 
returned success, but Slave_SQL_State and Executed_log_entries were not 
modified yet. 
Fixing it by adding a wait on the expected Executed_log_entries value.

expression to a _bin ENUM column

in mysql_upgrade: do FLUSH PRIVILEGES at the end, not together with
mysql_fix_privilege_tables

mysql-test/t/mysql_upgrade-6984.opt:
  use a dummy second option to force server restart after the test

skip qsort if the sort key has zero length

* use the same HAVE_C/CXX_ variables for compiler flag tests as the rest of
  the server and tokudb - to use cached results
* plugin's name should be "mroonga" not "ha_mroonga"
* don't use set_property(TARGET plugin_name ...), it aborts cmake when a plugin
  id disabled, because the target doesn't exists in that case

result: mroonga can now be disabled from cmake command line

try the first unique key as a surrogate PK *before* disabling extended
keys because of missing PK

1. remove find_mysql_client (from a bad merge)
2. use $mysql_command

disable binlogging when loading help tables

update mysql_system_tables_fix.sql to match mysql_system_tables.sql