Flutter unusual error in errors_patch.dart

Question

whenver I run my application, I run into this error in errors_patch.dart

  external static Never _throw(Object error, StackTrace stackTrace);

here is my entire file if it helps

import 'dart:convert';
import 'dart:io';

import 'package:firebase_storage/firebase_storage.dart';
import 'package:flutter/material.dart';
import 'package:just_audio/just_audio.dart';
import 'package:path_provider/path_provider.dart';

class PlayAudioBookScreen extends StatefulWidget {
  final Map<String, dynamic> initialChapterData;
  final Map<String, dynamic> audioBookData;
  const PlayAudioBookScreen(this.initialChapterData, this.audioBookData, {super.key});

  @override
  State<PlayAudioBookScreen> createState() => PlayAudioBookScreenState();
}

class PlayAudioBookScreenState extends State<PlayAudioBookScreen> {
  AudioPlayer player = AudioPlayer();
  bool playing = true;
  double sliderPos = 0;
  String bookTitle = "";
  String chapterTitle = "";
  String author = "";
  String audioFileLocalPath = "";
  String audioFileFirebasePath = "";
  int audioFileDuration = 0; // is in milliseconds
  Map<String, dynamic> currentChapterData = jsonDecode("{}");
  // in the below, bear in mind im limited by the variables (and equivalently the parameters) of the
  // PlayAudioBookScreen class must be final, so i cant just update the chapterData variable to the
  // next chapters data when reaching the end of the file.
  // a possible way of modifying the current chapter data used by the widget on the fly is by doing what
  // ive done with the commented out chapterData2 variable below here. just make a chapterData2 variable
  // like this, initialize it to widget.chapterData inside initState(), and then update it to the next
  // chapters data when reaching the end of the file.
  // other options would be to pop this screen and push a new one with the next chapters data, or to
  // have some global state management system like provider or bloc that i can consult to ask what
  // chapter where on now.
  // or even just provide the chapter number as a parameter called startChapter or sth, and inside the
  // state class have a "currentChapter" variable that is initialized to startChapter, and then updated
  // accordingly, and just get the chapter data of the currentChapter variable from audioBookData on an
  // adhoc basis.

  @override
  void initState() {
    bookTitle = widget.audioBookData["title"];
    author = widget.audioBookData["author"];
    currentChapterData = widget.initialChapterData;
    chapterTitle = currentChapterData["title"];
    audioFileLocalPath = currentChapterData["localPath"];
    audioFileFirebasePath = currentChapterData["firebasePath"];
    setupPlayer();
    super.initState();
  }

  void setupPlayer() async {
    Directory appDocDir = await getApplicationDocumentsDirectory();
    File audioFile = File("${appDocDir.path}/$audioFileLocalPath");
    if (!await audioFile.exists()) {
      // should have some error handling here if the download is unsuccessful in case the user is online,
      // maybe in other places of the app too <skull emoji>
      audioFile.create(recursive: true);
      print("come in here3");
      Reference audioFileFirebaseRef = FirebaseStorage.instance.ref(audioFileFirebasePath);
      await audioFileFirebaseRef.writeToFile(audioFile);
    }
    await player.setUrl(audioFile.path);
    player.createPositionStream();

    audioFileDuration = player.duration!.inMilliseconds;
    player.positionStream.listen((position) {
      if (position.inMilliseconds >= audioFileDuration) {
        if (int.parse(currentChapterData["chapterNumber"]) < widget.audioBookData["chapters"].length) {
          print("come in here");
          int nextChapterNumber = int.parse(currentChapterData["chapterNumber"]) + 1;
          print("I see this print statement");
          setupNewChapter(widget.audioBookData["chapters"][nextChapterNumber]);
        } else {
          print("acc here");
          player.pause();
          setState(() {
            sliderPos = audioFileDuration.toDouble();
            playing = false;
          });
        }
      } else {
        setState(() {
          sliderPos = position.inMilliseconds.toDouble();
        });
      }
    });

    player.play();
    setState(() {
      playing = true;
    });
  }

  void setupNewChapter(Map<String, dynamic> chapterData) {
    print("but dont see this print statement");
    currentChapterData = chapterData;
    print("come in here3");
    chapterTitle = currentChapterData["title"];
    print("come in her4S");
    audioFileLocalPath = currentChapterData["localPath"];
    print("come in here2");
    audioFileFirebasePath = currentChapterData["firebasePath"];
    print("come in here2");
    setupPlayer();
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      body: Column(children: [
        const SizedBox(height: 80),
        Text(bookTitle, style: const TextStyle(fontWeight: FontWeight.bold)),
        Text(chapterTitle, style: const TextStyle(fontWeight: FontWeight.bold)),
        Text("by $author"),
        const SizedBox(height: 20),
        playing
            ? IconButton(
                icon: const Icon(Icons.pause),
                onPressed: () async {
                  player.pause();
                  setState(() {
                    playing = false;
                  });
                },
              )
            : IconButton(
                icon: const Icon(Icons.play_arrow),
                onPressed: () async {
                  player.play();
                  setState(() {
                    playing = true;
                  });
                },
              ),
        Slider(
            min: 0,
            max: audioFileDuration.toDouble(),
            value: sliderPos,
            onChanged: (value) async {
              await player.seek(Duration(milliseconds: value.toInt()));
            }),
      ]),
    );
  }
}

but there doesn't seem to be any explanation online that I can find as to what this error means. I have put print statements and I see up to the print statement that says "I see this print statement" but then I dont see the one that says "but I dont see this one"