Remove complex weakref hacks, add intermediate object for communication with child threads while still allowing destruction.
Remove complex weakref hacks, add intermediate object for communication with
child threads while still allowing destruction.


git-svn-id: 55198a34599dbf839a02c2a2ff0bd06dff76438e@318 960bbd1a-3921-0410-93bb-a35bc832efea

google/mysql-tools,google/mysql-tools