Steps to Reproduce

run command: flutter run

Flutter app can start normally，but it throw a exception.
I try three android devices, but all have the same exception.

Logs

Unhandled exception:
Exception: Error connecting to observatory: WebSocketChannelException: WebSocketChannelException: WebSocketException: Connection to 'http://127.0.0.1:8104/ws#' was not upgraded to websocket
#0 throwToolExit (package:flutter_tools/src/base/common.dart:29)
#1 VM.invokeRpcRaw (package:flutter_tools/src/vmservice.dart:738)

#2 VM._fetchDirect (package:flutter_tools/src/vmservice.dart:566)

#3 ServiceObject.reload (package:flutter_tools/src/vmservice.dart:414)

#4 VMService.getVM (package:flutter_tools/src/vmservice.dart:243)
#5 FlutterDevice.getVMs (package:flutter_tools/src/resident_runner.dart:88)

#6 ResidentRunner.connectToServiceProtocol (package:flutter_tools/src/resident_runner.dart:584)

#7 HotRunner.attach (package:flutter_tools/src/run_hot.dart:106)

#8 HotRunner.run (package:flutter_tools/src/run_hot.dart:209)

#9 AppDomain.startApp. (package:flutter_tools/src/commands/daemon.dart:418)

#10 AppContext._run (package:flutter_tools/src/base/context.dart:76)

#11 AppContext.runInZone. (package:flutter_tools/src/base/context.dart:66)
#12 _rootRun (dart:async/zone.dart:1120)
#13 _CustomZone.run (dart:async/zone.dart:1001)
#14 runZoned (dart:async/zone.dart:1467)
#15 AppContext.runInZone (package:flutter_tools/src/base/context.dart:65)
#16 AppInstance._runInZone (package:flutter_tools/src/commands/daemon.dart:774)
#17 AppDomain.startApp (package:flutter_tools/src/commands/daemon.dart:416)

#18 RunCommand.runCommand (package:flutter_tools/src/commands/run.dart:267)

#19 FlutterCommand.verifyThenRunCommand (package:flutter_tools/src/runner/flutter_command.dart:239)

#20 RunCommand.verifyThenRunCommand (package:flutter_tools/src/commands/run.dart:232)

#21 FlutterCommand.run (package:flutter_tools/src/runner/flutter_command.dart:181)

#22 CommandRunner.runCommand (package:args/command_runner.dart:194)

#23 FlutterCommandRunner.runCommand (package:flutter_tools/src/runner/flutter_command_runner.dart:276)

#24 CommandRunner.run. (package:args/command_runner.dart:109)
#25 new Future.sync (dart:async/future.dart:222)
#26 CommandRunner.run (package:args/command_runner.dart:109)
#27 FlutterCommandRunner.run (package:flutter_tools/src/runner/flutter_command_runner.dart:161)
#28 run. (package:flutter_tools/executable.dart:143)

#29 AppContext._run (package:flutter_tools/src/base/context.dart:76)

#30 AppContext.runInZone. (package:flutter_tools/src/base/context.dart:66)
#31 _rootRun (dart:async/zone.dart:1120)
#32 _CustomZone.run (dart:async/zone.dart:1001)
#33 runZoned (dart:async/zone.dart:1467)
#34 AppContext.runInZone (package:flutter_tools/src/base/context.dart:65)
#35 run (package:flutter_tools/executable.dart:114)

#36 main (package:flutter_tools/executable.dart:67)

#37 main (file:///E:/flutter-workspace/libs/flutter/packages/flutter_tools/bin/flutter_tools.dart:16)
#38 _startIsolate. (dart:isolate-patch/isolate_patch.dart:263)
#39 _RawReceivePortImpl._handleMessage (dart:isolate-patch/isolate_patch.dart:151)

Flutter Doctor

E:\flutter-workspace\secret>flutter doctor
[√] Flutter (on Microsoft Windows [Version 6.1.7601], locale zh-CN, channel master)
• Flutter at E:\flutter-workspace\libs\flutter
• Framework revision c44aa26 (7 hours ago), 2017-09-22 15:33:50 -0700
• Engine revision 0a6e415
• Tools Dart version 1.25.0-dev.11.0

[√] Android toolchain - develop for Android devices (Android SDK 25.0.3)
• Android SDK at E:\Android\sdk
• Platform android-25, build-tools 25.0.3
• Java binary at: E:\android-studio\jre\bin\java
• Java version OpenJDK Runtime Environment (build 1.8.0_112-release-736)

[√] Android Studio (version 3.0)
• Android Studio at E:\android-studio
• Java version OpenJDK Runtime Environment (build 1.8.0_112-release-736)

[√] IntelliJ IDEA Ultimate Edition (version 2017.2)
• Flutter plugin version 17.0
• Dart plugin version 172.4155.35

[√] Connected devices
• PRO 6 Plus • M960BDPN2223K • android-arm • Android 6.0.1 (API 23)
• PRO 6 Plus • 172.18.8.159:5555 • android-arm • Android 6.0.1 (API 23)

For more information about diagnosing and reporting Flutter bugs, please see https://flutter.io/bug-reports/.