Workaround to prevent NSError from losing its UserInfo
Workaround to prevent NSError from losing its UserInfo

This is a workaround for rdar://22708537

calebd/ReactiveCocoa,walkingsmarts/ReactiveCocoa,llb1119/test,calebd/ReactiveCocoa,Farteen/ReactiveCocoa,RuiAAPeres/ReactiveCocoa,victorlin/ReactiveCocoa,ikesyo/ReactiveCocoa,paulyoung/ReactiveCocoa,paulyoung/ReactiveCocoa,tzongw/ReactiveCocoa,Farteen/ReactiveCocoa,yonekawa/ReactiveCocoa,walkingsmarts/ReactiveCocoa,ohwutup/ReactiveCocoa,Juraldinio/ReactiveCocoa,Juraldinio/ReactiveCocoa,rpowelll/ReactiveCocoa,andersio/ReactiveCocoa,yonekawa/ReactiveCocoa,ReactiveCocoa/ReactiveSwift,ikesyo/ReactiveCocoa,smilypeda/ReactiveCocoa,kevin-zqw/ReactiveCocoa,llb1119/test,calebd/ReactiveCocoa,paulyoung/ReactiveCocoa,sandyway/ReactiveCocoa,ohwutup/ReactiveCocoa,walkingsmarts/ReactiveCocoa,RuiAAPeres/ReactiveCocoa,ohwutup/ReactiveCocoa,natestedman/ReactiveCocoa,ReactiveCocoa/ReactiveSwift,tonyarnold/ReactiveCocoa,natestedman/ReactiveCocoa,RuiAAPeres/ReactiveCocoa,smilypeda/ReactiveCocoa,tzongw/ReactiveCocoa,rpowelll/ReactiveCocoa,Farteen/ReactiveCocoa,llb1119/test,sandyway/ReactiveCocoa,ReactiveCocoa/ReactiveSwift,rpowelll/ReactiveCocoa,sandyway/ReactiveCocoa,victorlin/ReactiveCocoa,andersio/ReactiveCocoa,yonekawa/ReactiveCocoa,tonyarnold/ReactiveCocoa,tonyarnold/ReactiveCocoa,natestedman/ReactiveCocoa,andersio/ReactiveCocoa,smilypeda/ReactiveCocoa,kevin-zqw/ReactiveCocoa,victorlin/ReactiveCocoa,Juraldinio/ReactiveCocoa,kevin-zqw/ReactiveCocoa,tzongw/ReactiveCocoa