RestKit/RestKit — pull request #1247 by jcoleman (2013-02-20 21:18:59+00:00)
Title: Fix deadlocking resulting from executing blocking operation on the main thread.

The MOC at play here has the concurrency type of NSMainQueueConcurrencyType. And this method can easily be triggered by the main thread (e.g. the success callback calling RKObjectRequestOperation#array). So if we use NSManagedObjectContext#performBlockAndWait:, then we'll deadlock.