android 测试环境正常，打包后消息发送不出去

[liumingsongning]

``2020-09-07 09:12:25.955 2184-2618/? D/NetworkController.MobileSignalController(1): 4G level = 5 2020-09-07 09:12:27.389 10040-10040/? W/adbd: timeout expired while flushing socket, closing 2020-09-07 09:12:27.753 15692-15692/? D/i: onMethodCall openClient， args:{r=false, clientId=Tom, signRegistry={sessionOpen=false, conversation=false}} 2020-09-07 09:12:27.753 15692-15692/? D/g: openClient... 2020-09-07 09:12:27.754 15692-15692/? D/k: add request cache. client=Tom, conv=null, request=-65534 2020-09-07 09:12:27.754 15692-15692/? E/e: session error:java.lang.IllegalStateException: Connection Lost 2020-09-07 09:12:27.754 15692-15692/? D/g: enter onOperationCompleted with clientId=Tom, convId=null, requestId=-65534, operation=CLIENT_OPEN 2020-09-07 09:12:27.754 15692-15692/? D/i: client open result: {clientId=Tom} 2020-09-07 09:12:27.755 15692-15722/? E/flutter: [ERROR:flutter/lib/ui/ui_dart_state.cc(166)] Unhandled Exception: LC.RTM.Exception( code: 0, essage: java.lang.IllegalStateException: Connection Lost, details: Connection Lost, ) #0 _Utilities.call (package:leancloud_official_plugin/src/client.dart:122) #1 Client.open (package:leancloud_official_plugin/src/client.dart:454) #2 _MyHomePageState._incrementCounter (package:im/main.dart:59) 2020-09-07 09:12:28.527 1942-2078/? I/MiuiNetworkPolicy: bandwidth: 0 KB/s, Max bandwidth: 1826 KB/s 2020-09-07 09:12:28.974 2184-2618/? D/NetworkController.MobileSignalController(1): 4G level = 5 2020-09-07 09:12:29.004 2184-2184/? D/SignalClusterView: updateMobileTypeImage 0 2020-09-07 09:12:29.022 2184-2184/? I/chatty: uid=1000(system) com.android.systemui identical 12 lines 2020-09-07 09:12:29.022 2184-2184/? D/SignalClusterView: updateMobileTypeImage 0 2020-09-07 09:12:29.649 18943-18943/? I/subsystem_ramdump: Usage:./system/bin/subsystem_ramdump [arg1] [arg2] [arg3]

[zapcannon87]

@jwfing