facebook/facebook-ios-sdk — pull request #488 by yyjim (2012-09-22 09:07:46+00:00)
Title: Fixed potential memory leak and strange callback from FBFrictionlessRequestSettings

in FBFrictionlessRequestSettings

FBRequest doesn't have a interface to cancel the request and callback will happen asynchronously.

so it should set activeRequest delegate to nil to avoid callback send to deallocated object.