deadlocks
Backport of revno: 2617.68.35
The problem was that if one connection is running a multi-statement
transaction which involves a single partitioned table, and another
connection attempts to alter the table to drop a non-existing partition,
(which of course will fail), the first connection still gets
ER_LOCK_DEADLOCK and cannot proceed anymore.
This bug is no longer reproducable. This has also been tested with the
patch for Bug#46654 "False deadlock on concurrent DML/DDL with partitions,
inconsistent behavior" which concerned a similar problem but where the
ALTER TABLE is semantically correct.
Test case added in partition_sync.test.
