Linux web_long_running_tests_2_5 flakes on Unexpected character #97318
Description
(part of #97036)
These data is based on Q4 2021 flakes that happened from 10/01/2021 to 01/13/2022
1 flake on timeout: 2380 (happened on 12/10/2021)
▌22:28:23▐ RUNNING: cd dev/integration_tests/web; ../../../bin/flutter run --debug -d chrome --web-run-headless --dart-define=FLUTTER_WEB_USE_SKIA=false --dart-define=FLUTTER_WEB_AUTO_DETECT=false -t lib/web_directory_loading.dart
Launching lib/web_directory_loading.dart on Chrome in debug mode...
Waiting for connection from debug service on Chrome... 617ms
FormatException: Unexpected character (at character 1)
<!DOCTYPE HTML>
^
#0 _ChunkedJsonParser.fail (dart:convert-patch/convert_patch.dart:1405:5)
#1 _ChunkedJsonParser.parseNumber (dart:convert-patch/convert_patch.dart:1272:9)
#2 _ChunkedJsonParser.parse (dart:convert-patch/convert_patch.dart:937:22)
#3 _parseJson (dart:convert-patch/convert_patch.dart:40:10)
#4 JsonDecoder.convert (dart:convert/json.dart:612:36)
#5 JsonCodec.decode (dart:convert/json.dart:216:41)
#6 jsonDecode (dart:convert/json.dart:155:10)
#7 ChromeConnection.getTabs (package:webkit_inspection_protocol/webkit_inspection_protocol.dart:44:10)
<asynchronous suspension>
#8 ChromeConnection.getTab (package:webkit_inspection_protocol/webkit_inspection_protocol.dart:57:25)
<asynchronous suspension>
#9 ChromiumLauncher._connect (package:flutter_tools/src/web/chrome.dart:401:9)
<asynchronous suspension>
#10 ChromiumDevice.startApp (package:flutter_tools/src/web/web_device.dart:134:17)
<asynchronous suspension>
#11 ResidentWebRunner.run.<anonymous closure> (package:flutter_tools/src/isolated/resident_web_runner.dart:307:9)
<asynchronous suspension>
#12 asyncGuard.<anonymous closure> (package:flutter_tools/src/base/async_guard.dart:111:24)
<asynchronous suspension>
Unable to connect to Chrome debug port: 35881
FormatException: Unexpected character (at character 1)
<!DOCTYPE HTML>
^