自己的APP昨天更新leancloud sdk 到3.15.1 后，app 再次打开后无法显示。

刚使用你们的chatkit android demo 测试，发现了同样的问题。重现步骤：
1. leanchat （更新leancloud sdk 到3.15.1）安装后首次输入密码登录（该步骤没有问题）
2. 退出后，再次运行，即会卡在白屏界面，app 无法 打开. 日志循环输出：

11-18 11:16:14.153 22347-22347/com.avoscloud.chat E/AVUser: AVUser->getCurrentUser->197: {"@type":"com.avoscloud.chat.model.LeanchatUser","anonymous":false,"authenticated":true,"className":"User","createdAt":"2016-09-12T19:51:31.032Z","dataAvailable":false,"dataReady":false,"fetchWhenSave":false,"filesToSave":[],"geoPoint":{"latitude":31.102675D,"longitude":121.513821D},"mobilePhoneVerified":false,"objectId":"57d696c3128fe10055319ea0","operationQueue":{"@type":"java.util.HashMap"},"roles":[],"serverData":{"@type":"java.util.HashMap","emailVerified":false,"installation":{ "@type":"com.avos.avoscloud.AVInstallation","objectId":"ShO4ocTgqCHQA2I2LrjGY9N7CDOA9Jg2","updatedAt":null,"createdAt":null,"className":"Installation","serverData":{"@type":"java.util.HashMap","className":"_Installation","deviceType":"android","installationId":"114d2d42181296c61eb5026a49c0cf6a","timeZone":"Asia/Shanghai"}},"location":{"@type":"com.avos.avoscloud.AVGeoPoint","latitude":31.102675D,"longitude":121.513821D},"mobilePhoneVerified":false,"sessionToken":"bvzkiquyjslf2zicekbyrgbx5","username":"家里"},"sessionToken":"bvzkiquyjslf2zicekbyrgbx5","updatedAt":"2016-11-01T13:34:04.220Z","username":"家里","uuid":"58677c6d-92bf-4d8d-a3b9-a453a0ce2362"} err:com.alibaba.fastjson.JSONException: set property error, roles
11-18 11:16:14.153 22347-22347/com.avoscloud.chat I/art: Rejecting re-init on previously-failed class java.lang.Class
11-18 11:16:14.263 22347-22353/com.avoscloud.chat W/art: Suspending all threads took: 106.080ms
11-18 11:16:14.283 22347-22357/com.avoscloud.chat I/art: Background partial concurrent mark sweep GC freed 300642(17MB) AllocSpace objects, 4(2MB) LOS objects, 18% free, 71MB/87MB, paused 571.685ms total 1.251s
11-18 11:16:14.403 22347-22357/com.avoscloud.chat W/art: Suspending all threads took: 119.185ms
11-18 11:16:14.523 22347-22353/com.avoscloud.chat W/art: Suspending all threads took: 106.000ms
11-18 11:16:15.023 22347-22353/com.avoscloud.chat W/art: Suspending all threads took: 200.122ms
11-18 11:16:15.573 22347-22353/com.avoscloud.chat W/art: Suspending all threads took: 250.235ms
11-18 11:16:15.583 22347-22357/com.avoscloud.chat W/art: Suspending all threads took: 8.550ms
11-18 11:16:15.793 22347-22347/com.avoscloud.chat E/AVUser: AVUser->getCurrentUser->197: {"@type":"com.avoscloud.chat.model.LeanchatUser","anonymous":false,"authenticated":true,"className":"User","createdAt":"2016-09-12T19:51:31.032Z","dataAvailable":false,"dataReady":false,"fetchWhenSave":false,"filesToSave":[],"geoPoint":{"latitude":31.102675D,"longitude":121.513821D},"mobilePhoneVerified":false,"objectId":"57d696c3128fe10055319ea0","operationQueue":{"@type":"java.util.HashMap"},"roles":[],"serverData":{"@type":"java.util.HashMap","emailVerified":false,"installation":{ "@type":"com.avos.avoscloud.AVInstallation","objectId":"ShO4ocTgqCHQA2I2LrjGY9N7CDOA9Jg2","updatedAt":null,"createdAt":null,"className":"Installation","serverData":{"@type":"java.util.HashMap","className":"_Installation","deviceType":"android","installationId":"114d2d42181296c61eb5026a49c0cf6a","timeZone":"Asia/Shanghai"}},"location":{"@type":"com.avos.avoscloud.AVGeoPoint","latitude":31.102675D,"longitude":121.513821D},"mobilePhoneVerified":false,"sessionToken":"bvzkiquyjslf2zicekbyrgbx5","username":"家里"},"sessionToken":"bvzkiquyjslf2zicekbyrgbx5","updatedAt":"2016-11-01T13:34:04.220Z","username":"家里","uuid":"58677c6d-92bf-4d8d-a3b9-a453a0ce2362"} err:com.alibaba.fastjson.JSONException: set property error, roles
11-18 11:16:15.793 22347-22347/com.avoscloud.chat I/art: Rejecting re-init on previously-failed class java.lang.Class
11-18 11:16:15.803 22347-22357/com.avoscloud.chat I/art: Background sticky concurrent mark sweep GC freed 124(313KB) AllocSpace objects, 1(588KB) LOS objects, 0% free, 90MB/90MB, paused 213.214ms total 774.274ms
11-18 11:16:15.943 22347-22357/com.avoscloud.chat W/art: Suspending all threads took: 140.732ms
11-18 11:16:16.763 22347-22353/com.avoscloud.chat W/art: Suspending all threads took: 440.080ms
11-18 11:16:16.933 22347-22353/com.avoscloud.chat W/art: Suspending all threads took: 105.167ms
11-18 11:16:16.933 22347-22357/com.avoscloud.chat I/art: Background partial concurrent mark sweep GC freed 601073(34MB) AllocSpace objects, 9(5MB) LOS objects, 23% free, 53MB/69MB, paused 183.418ms total 903.303ms
11-18 11:16:17.043 22347-22357/com.avoscloud.chat W/art: Suspending all threads took: 105.419ms
11-18 11:16:17.343 22347-22353/com.avoscloud.chat W/art: Suspending all threads took: 21.038ms