Conflict resolution doesn't need to read new pickle data from the database

[jamadden]

This is because the new pickled data is already guaranteed to be in the local cache (an AutoTemporaryFile/SpooledTemporaryFile).

Upsides: less network IO (and at least in some DBs, the pickled data is base64 encoded, so lower overhead to decode). So theoretically it should be faster, especially if there are many conflicts.

Downsides: changing the conflict resolution code. On the other hand, this code path is pretty well tested.