Review: ensure reentrant, rearrange coroutine job management

mirai-core-qqandroid/src/commonMain/kotlin/net/mamoe/mirai/qqandroid/network/QQAndroidBotNetworkHandler.kt

@@ -180,6 +180,7 @@ internal class QQAndroidBotNetworkHandler(bot: QQAndroidBot) : BotNetworkHandler
     // caches
     private val _pendingEnabled = atomic(true)
     internal val pendingEnabled get() = _pendingEnabled.value
+    @Volatile
     internal var pendingIncomingPackets: LockFreeLinkedList<KnownPacketFactories.IncomingPacket<*>>? =
         LockFreeLinkedList()
 
@@ -191,7 +192,13 @@ internal class QQAndroidBotNetworkHandler(bot: QQAndroidBot) : BotNetworkHandler
         bot.friends.delegate.clear()
         bot.groups.delegate.clear()
 
-        val friendListJob = launch {
+        if (!pendingEnabled) {
+            pendingIncomingPackets = LockFreeLinkedList()
+            _pendingEnabled.value = true
+        }
+
+        coroutineScope {
+            launch {
                 lateinit var loadFriends: suspend () -> Unit
                 // 不要用 fun, 不要 join declaration, 不要用 val, 编译失败警告
                 loadFriends = suspend loadFriends@{
@@ -239,7 +246,7 @@ internal class QQAndroidBotNetworkHandler(bot: QQAndroidBot) : BotNetworkHandler
                 loadFriends()
             }
 
-        val groupJob = launch {
+            launch {
                 try {
                     logger.info("开始加载群组列表与群成员列表")
                     val troopListData = FriendList.GetTroopListSimplify(bot.client)
@@ -301,8 +308,7 @@ internal class QQAndroidBotNetworkHandler(bot: QQAndroidBot) : BotNetworkHandler
                     logger.error(e)
                 }
             }
-
-        joinAll(friendListJob, groupJob)
+        }
 
         withTimeoutOrNull(5000) {
             lateinit var listener: Listener<PacketReceivedEvent>