Revert "Use `io.ktor.utils.io` than `kotlinx.io`"

This reverts commit 6a85769e

gradle.properties

@@ -10,6 +10,7 @@ kotlinVersion=1.3.61
 serializationVersion=0.14.0
 coroutinesVersion=1.3.3
 atomicFuVersion=0.14.1
+kotlinXIoVersion=0.1.16
 coroutinesIoVersion=0.1.16
 # utility
 ktorVersion=1.3.1
\ No newline at end of file

mirai-core-qqandroid/src/commonMain/kotlin/net/mamoe/mirai/qqandroid/network/protocol/packet/login/Heartbeat.kt

@@ -9,7 +9,7 @@
 
 package net.mamoe.mirai.qqandroid.network.protocol.packet.login
 
-import io.ktor.utils.io.core.ByteReadPacket
+import kotlinx.io.core.ByteReadPacket
 import net.mamoe.mirai.data.Packet
 import net.mamoe.mirai.qqandroid.QQAndroidBot
 import net.mamoe.mirai.qqandroid.network.QQAndroidClient

mirai-core/src/commonMain/kotlin/net.mamoe.mirai/utils/io/ByteArrayPool.kt

@@ -11,7 +11,8 @@
 
 package net.mamoe.mirai.utils.io
 
-import io.ktor.utils.io.pool.DefaultPool
+import kotlinx.io.pool.DefaultPool
+import kotlinx.io.pool.ObjectPool
 import net.mamoe.mirai.utils.MiraiInternalAPI
 
 /**

mirai-core/src/commonMain/kotlin/net.mamoe.mirai/utils/io/input.kt

@@ -13,11 +13,11 @@
 
 package net.mamoe.mirai.utils.io
 
-import io.ktor.utils.io.charsets.Charset
-import io.ktor.utils.io.charsets.Charsets
-import io.ktor.utils.io.core.*
-import io.ktor.utils.io.pool.useInstance
 import kotlinx.io.OutputStream
+import kotlinx.io.charsets.Charset
+import kotlinx.io.charsets.Charsets
+import kotlinx.io.core.*
+import kotlinx.io.pool.useInstance
 import net.mamoe.mirai.utils.MiraiDebugAPI
 import net.mamoe.mirai.utils.MiraiInternalAPI
 import kotlin.contracts.ExperimentalContracts