Remove isOnline

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

@@ -44,9 +44,6 @@ internal class QQImpl(bot: QQAndroidBot, override val coroutineContext: Coroutin
         TODO("not implemented")
     }
 
-    override val isOnline: Boolean
-        get() = true
-
     override suspend fun queryProfile(): Profile {
         TODO("not implemented")
     }

mirai-core/src/commonMain/kotlin/net.mamoe.mirai/contact/QQ.kt

@@ -22,9 +22,9 @@ import net.mamoe.mirai.data.Profile
  */
 interface QQ : Contact, CoroutineScope {
     /**
-     * 是否在线. 这个属性的值将会与服务器同步更新.
+     * QQ 号码
      */
-    val isOnline: Boolean
+    override val id: Long
 
     /**
      * 请求头像下载链接