致命异常：NSInvalidArgumentException
*** [NS JSONSerialization dataWithJSONObject：options：error：]：value参数为nil
*** [NS JSONSerialization dataWithJSONObject：options：error：]：value参数为nil
基金会[NSJSONSerialization dataWithJSONObject：options：error：] 84
ProjectName – [ANSWriteEventOperation logLineWithTimestamp：eventName：payloadDictionary：] 72
ProjectName – [ANSWriteEventOperation generateFormattedLogLineWithMetdata：timestamp：] 142
ProjectName – [ANSWriteEventOperation initWithEvent：Metadata：logFileUrl：] 200
项目名
__38- [ANSAnswersController logCrashEvent：] _ block_invoke 600
基金会NSBLOCKOPERATION_IS_CALLING_OUT_TO_A_BLOCK 8
解决方法
根据Crashlytics开发人员的说法,这已在3.8.2中修复.看到这个特殊的开发者评论
https://twittercommunity.com/t/crash-io-answers-eventqueue-nsoperation-qos-background/74765/7
