Layout explorer exception in DevTools

Debugging CupertinoApp on android emulator, mixed usage Theme.of and CupertinoThemeData.of
I was trying something.

```console
[√] Flutter (Channel stable, 2.0.4, on Microsoft Windows [Version 10.0.19042.867], locale bg-BG)
[√] Android toolchain - develop for Android devices (Android SDK version 30.0.2)
[√] Chrome - develop for the web
[√] Android Studio (version 4.1.0)
[√] VS Code, 64-bit edition (version 1.55.1)
[√] Connected device (2 available)
```
In chrome dev tools I see this exception as soon I click on a widget in the left tree.

logs

```console
main.dart.js:54020 ext.flutter.inspector.getLayoutExplorerNode: (-32000) Server error
'package:flutter/src/foundation/stack_frame.dart': Failed assertion: line 207 pos 12: 'match != null': Expected flutter/devtools#40 Eval..getLayoutExplorerNode. () to match RegExp: pattern=^#(\d+) +(.+) \((.+?):?(\d+){0,1}:?(\d+){0,1}\)$ flags=.
#0 _AssertionError._doThrowNew (dart:core-patch/errors_patch.dart:46:39)
flutter/devtools#1 _AssertionError._throwNew (dart:core-patch/errors_patch.dart:36:5)
flutter/devtools#2 StackFrame.fromStackTraceLine (package:flutter/src/foundation/stack_frame.dart:207:12)
flutter/devtools#3 MappedIterator.moveNext (dart:_internal/iterable.dart:389:20)
flutter/devtools#4 WhereTypeIterator.moveNext (dart:_internal/iterable.dart:866:20)
flutter/devtools#5 new _GrowableList._ofOther (dart:core-patch/growable_array.dart:198:26)
flutter/devtools#6 new _GrowableList.of (dart:core-patch/growable_array.dart:152:26)
flutter/devtools#7 new List.of (dart:core-patch/array_patch.dart:50:28)
flutter/devtools#8 Iterable.toList (dart:core/iterable.dart:366:12)
flutter/devtools#9 StackFrame.fromStackString (package:flutter/src/foundation/stack_frame.dart:95:10)
flutter/devtools#10 FlutterError.defaultStackFilter (package:flutter/src/foundation/assertions.dart:1016:54)
flutter/devtools#11 DiagnosticsStackTrace._applyStackFilter (package:flutter/src/foundation/assertions.dart:1187:43)
flutter/devtools#12 new DiagnosticsStackTrace (package:flutter/src/foundation/assertions.dart:1162:17)
flutter/devtools#13 FlutterErrorDetails.debugFillProperties (package:flutter/src/foundation/assertions.dart:683:22)
flutter/devtools#14 DiagnosticableNode.builder. (package:flutter/src/foundation/diagnostics.dart:2945:17)
flutter/devtools#15 DiagnosticableNode.builder (package:flutter/src/foundation/diagnostics.dart:2948:8)
flutter/devtools#16 _FlutterErrorDetailsNode.builder (package:flutter/src/foundation/assertions.dart:1209:56)
flutter/devtools#17 DiagnosticableNode.emptyBodyDescription (package:flutter/src/foundation/diagnostics.dart:2959:77)
flutter/devtools#18 DiagnosticsNode.toJsonMap. (package:flutter/src/foundation/diagnostics.dart:1578:13)
flutter/devtools#19 DiagnosticsNode.toJsonMap (package:flutter/src/foundation/diagnostics.dart:1607:6)
flutter/devtools#20 WidgetInspectorService._nodeToJson (package:flutter/src/widgets/widget_inspector.dart:1499:18)
flutter/devtools#21 WidgetInspectorService._reportError (package:flutter/src/widgets/widget_inspector.dart:919:44)
flutter/devtools#22 FlutterError.reportError (package:flutter/src/foundation/assertions.dart:1103:15)
flutter/devtools#23 BindingBase.registerServiceExtension. (package:flutter/src/foundation/binding.dart:607:22)

```

I was expecting that I should be able to run a cupertino app in android emulator, as it is just UI, my app doesn't have added native plugins that I'm using.

Reproduce el fallo en Chrome DevTools abriendo el explorador de diseño y haciendo clic en un widget del árbol izquierdo. Empieza con getLayoutExplorerNode y el manejo de la traza de pila mencionado en package:flutter/src/foundation/stack_frame.dart; después inspecciona los frames relacionados de assertions.dart y widget_inspector.dart; estará terminado cuando el explorador de diseño ya no produzca esta excepción.

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