Shopify/sarama — pull request #192 by eapache (2014-11-16 16:50:09+00:00)
Title: Add a mutex to SimpleProducer.SendMessage

The dumbest (and least performant) way to make SimpleProducer concurrency-safe.
The quick fix for the most concerning part of #187, since the proper concurrency
fix won't have any effect until we can do multiple requests in flight again
anyways.