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Compiler error when debugging build method during call to runApp

See original GitHub issue

Steps to Reproduce

I have this in main.dart in IntelliJ IDEA:

import 'package:flutter/widgets.dart';

void main() {
  runApp(MyWidget());
}

class MyWidget extends StatelessWidget {

  @override
  Widget build(BuildContext context) {
    return Container();
  }
}

I set a breakpoint on the return statement in build. When the debugger hits that point, I attempt to expand context in the debugger window or using the tooltip that pops up when I hover over context in the editor. When I do, the debugger disconnects and I get this error in my console:

14:52:41.736 9 info flutter.tools compiler message: Unhandled exception:
14:52:41.737 10 info flutter.tools compiler message: NoSuchMethodError: The getter 'className' was called on null.
14:52:41.737 11 info flutter.tools compiler message: Receiver: null
14:52:41.737 12 info flutter.tools compiler message: Tried calling: className
14:52:41.737 13 info flutter.tools compiler message: #0      Object.noSuchMethod (dart:core/runtime/libobject_patch.dart:48:5)
14:52:41.737 14 info flutter.tools compiler message: #1      serializeProcedure (package:front_end/src/fasta/kernel/utils.dart:82:29)
14:52:41.737 15 info flutter.tools compiler message: #2      FrontendCompiler.compileExpression (package:vm/frontend_server.dart:466:16)
14:52:41.737 16 info flutter.tools compiler message: <asynchronous suspension>
14:52:41.737 17 info flutter.tools compiler message: #3      _FlutterFrontendCompiler.compileExpression (package:frontend_server/server.dart:55:22)
14:52:41.737 18 info flutter.tools compiler message: #4      listenAndCompile.<anonymous closure> (package:vm/frontend_server.dart:664:20)
14:52:41.737 19 info flutter.tools compiler message: <asynchronous suspension>
14:52:41.737 20 info flutter.tools compiler message: #5      _RootZone.runUnaryGuarded (dart:async/zone.dart:1314:10)
14:52:41.737 21 info flutter.tools compiler message: #6      _BufferingStreamSubscription._sendData (dart:async/stream_impl.dart:336:11)
14:52:41.737 22 info flutter.tools compiler message: #7      _BufferingStreamSubscription._add (dart:async/stream_impl.dart:263:7)
14:52:41.737 23 info flutter.tools compiler message: #8      _SinkTransformerStreamSubscription._add (dart:async/stream_transformers.dart:68:11)
14:52:41.737 24 info flutter.tools compiler message: #9      _EventSinkWrapper.add (dart:async/stream_transformers.dart:15:11)
14:52:41.737 25 info flutter.tools compiler message: #10     _StringAdapterSink.add (dart:convert/string_conversion.dart:268:11)
14:52:41.737 26 info flutter.tools compiler message: #11     _LineSplitterSink._addLines (dart:convert/line_splitter.dart:154:13)
14:52:41.737 27 info flutter.tools compiler message: #12     _LineSplitterSink.addSlice (dart:convert/line_splitter.dart:129:5)
14:52:41.737 28 info flutter.tools compiler message: #13     StringConversionSinkMixin.add (dart:convert/string_conversion.dart:189:5)
14:52:41.737 29 info flutter.tools compiler message: #14     _SinkTransformerStreamSubscription._handleData (dart:async/stream_transformers.dart:120:24)
14:52:41.737 30 info flutter.tools compiler message: #15     _RootZone.runUnaryGuarded (dart:async/zone.dart:1314:10)
14:52:41.737 31 info flutter.tools compiler message: #16     _BufferingStreamSubscription._sendData (dart:async/stream_impl.dart:336:11)
14:52:41.737 32 info flutter.tools compiler message: #17     _BufferingStreamSubscription._add (dart:async/stream_impl.dart:263:7)
14:52:41.737 33 info flutter.tools compiler message: #18     _SinkTransformerStreamSubscription._add (dart:async/stream_transformers.dart:68:11)
14:52:41.737 34 info flutter.tools compiler message: #19     _EventSinkWrapper.add (dart:async/stream_transformers.dart:15:11)
14:52:41.737 35 info flutter.tools compiler message: #20     _StringAdapterSink.add (dart:convert/string_conversion.dart:268:11)
14:52:41.737 36 info flutter.tools compiler message: #21     _StringAdapterSink.addSlice (dart:convert/string_conversion.dart:273:7)
14:52:41.737 37 info flutter.tools compiler message: #22     _Utf8ConversionSink.addSlice (dart:convert/string_conversion.dart:348:20)
14:52:41.737 38 info flutter.tools compiler message: #23     _Utf8ConversionSink.add (dart:convert/string_conversion.dart:341:5)
14:52:41.737 39 info flutter.tools compiler message: #24     _ConverterStreamEventSink.add (dart:convert/chunked_conversion.dart:86:18)
14:52:41.738 40 info flutter.tools compiler message: #25     _SinkTransformerStreamSubscription._handleData (dart:async/stream_transformers.dart:120:24)
14:52:41.739 41 info flutter.tools compiler message: #26     _RootZone.runUnaryGuarded (dart:async/zone.dart:1314:10)
14:52:41.739 42 info flutter.tools compiler message: #27     _BufferingStreamSubscription._sendData (dart:async/stream_impl.dart:336:11)
14:52:41.739 43 info flutter.tools compiler message: #28     _BufferingStreamSubscription._add (dart:async/stream_impl.dart:263:7)
14:52:41.739 44 info flutter.tools compiler message: #29     _SyncStreamController._sendData (dart:async/stream_controller.dart:763:19)
14:52:41.739 45 info flutter.tools compiler message: #30     _StreamController._add (dart:async/stream_controller.dart:639:7)
14:52:41.739 46 info flutter.tools compiler message: #31     _StreamController.add (dart:async/stream_controller.dart:585:5)
14:52:41.740 47 info flutter.tools 
14:52:41.740 48 info flutter.tools compiler message: #32     _Socket._onData (dart:io/runtime/binsocket_patch.dart:1714:41)
14:52:41.742 49 info flutter.tools compiler message: #33     _RootZone.runUnaryGuarded (dart:async/zone.dart:1314:10)
14:52:41.742 50 info flutter.tools compiler message: #34     _BufferingStreamSubscription._sendData (dart:async/stream_impl.dart:336:11)
14:52:41.742 51 info flutter.tools compiler message: #35     _BufferingStreamSubscription._add (dart:async/stream_impl.dart:263:7)
14:52:41.742 52 info flutter.tools 
14:52:41.744 53 info flutter.tools compiler message: #36     _SyncStreamController._sendData (dart:async/stream_controller.dart:763:19)
14:52:41.744 54 info flutter.tools compiler message: #37     _StreamController._add (dart:async/stream_controller.dart:639:7)
14:52:41.744 55 info flutter.tools compiler message: #38     _StreamController.add (dart:async/stream_controller.dart:585:5)
14:52:41.744 56 info flutter.tools 
14:52:41.745 57 info flutter.tools compiler message: #39     new _RawSocket.<anonymous closure> (dart:io/runtime/binsocket_patch.dart:1276:33)
14:52:41.745 58 info flutter.tools compiler message: #40     _NativeSocket.issueReadEvent.issue (dart:io/runtime/binsocket_patch.dart:819:14)
14:52:41.745 59 info flutter.tools compiler message: #41     _microtaskLoop (dart:async/schedule_microtask.dart:41:21)
14:52:41.747 60 info flutter.tools 
14:52:41.747 61 info flutter.tools compiler message: #42     _startMicrotaskLoop (dart:async/schedule_microtask.dart:50:5)
14:52:41.747 62 info flutter.tools compiler message: #43     _runPendingImmediateCallback (dart:isolate/runtime/libisolate_patch.dart:115:13)
14:52:41.747 63 info flutter.tools compiler message: #44     _RawReceivePortImpl._handleMessage (dart:isolate/runtime/libisolate_patch.dart:172:5)
14:52:41.865 64 info flutter.tools Unhandled exception:
14:52:41.865 65 info flutter.tools SocketException: Write failed (OS Error: Broken pipe, errno = 32), port = 0
14:52:41.865 66 info flutter.tools #0      _rootHandleUncaughtError.<anonymous closure> (dart:async/zone.dart:1112:29)
14:52:41.865 67 info flutter.tools #1      _microtaskLoop (dart:async/schedule_microtask.dart:41:21)
14:52:41.865 68 info flutter.tools #2      _startMicrotaskLoop (dart:async/schedule_microtask.dart:50:5)
14:52:41.865 69 info flutter.tools #3      _runPendingImmediateCallback (dart:isolate/runtime/libisolate_patch.dart:115:13)
14:52:41.865 70 info flutter.tools #4      _RawReceivePortImpl._handleMessage (dart:isolate/runtime/libisolate_patch.dart:172:5)

Version info

[✓] Flutter (Channel beta, v0.7.3, on Mac OS X 10.13.6 17G65, locale en-US) [✓] Android toolchain - develop for Android devices (Android SDK 27.0.3) [✓] iOS toolchain - develop for iOS devices (Xcode 9.4.1) [✓] Android Studio (version 3.1) [✓] IntelliJ IDEA Community Edition (version 2018.2.3) [!] VS Code (version 1.24.1) [✓] Connected devices (1 available)