Revert "mod: exit"

This reverts commit 659c7363d5.

lib/services/audio_handler.dart

@@ -1,5 +1,3 @@
-import 'dart:io';
-
 import 'package:audio_service/audio_service.dart';
 import 'package:flutter/cupertino.dart';
 import 'package:hive/hive.dart';
@@ -60,13 +58,6 @@ class VideoPlayerServiceHandler extends BaseAudioHandler with SeekHandler {
     // await player.seekTo(position);
   }
 
-  @override
-  Future<void> onTaskRemoved() async {
-    if (Platform.isAndroid) {
-      exit(0);
-    }
-  }
-
   Future<void> setMediaItem(MediaItem newMediaItem) async {
     if (!enableBackgroundPlay) return;
     // print("此时调用栈为：");