Merge InnoDB 5.7 from mysql-5.7.9.

Contains also

MDEV-10547: Test multi_update_innodb fails with InnoDB 5.7

	The failure happened because 5.7 has changed the signature of
	the bool handler::primary_key_is_clustered() const
	virtual function ("const" was added). InnoDB was using the old
	signature which caused the function not to be used.

MDEV-10550: Parallel replication lock waits/deadlock handling does not work with InnoDB 5.7

	Fixed mutexing problem on lock_trx_handle_wait. Note that
	rpl_parallel and rpl_optimistic_parallel tests still
	fail.

MDEV-10156 : Group commit tests fail on 10.2 InnoDB (branch bb-10.2-jan)
  Reason: incorrect merge

MDEV-10550: Parallel replication can't sync with master in InnoDB 5.7 (branch bb-10.2-jan)
  Reason: incorrect merge

mysql-test/r/mysqld--help.result

@@ -108,9 +108,6 @@ The following options may be given as the first argument:
  --bulk-insert-buffer-size=# 
  Size of tree cache used in bulk insert optimisation. Note
  that this is a limit per thread!
- --changed-page-bitmaps[=name] 
- Enable or disable CHANGED_PAGE_BITMAPS plugin. One of:
- ON, OFF, FORCE (don't start if the plugin fails to load).
  --character-set-client-handshake 
  Don't ignore client side character set value sent during
  handshake.
@@ -1153,7 +1150,6 @@ binlog-row-event-max-size 1024
 binlog-row-image FULL
 binlog-stmt-cache-size 32768
 bulk-insert-buffer-size 8388608
-changed-page-bitmaps ON
 character-set-client-handshake TRUE
 character-set-filesystem binary
 character-sets-dir MYSQL_CHARSETSDIR/