Repository: flutter
Issue: UnsupportedError at _getItemFromOffset at package:flutter/src/widgets/list_wheel_scroll_view.dart
Labels: c: crash,framework,f: scrolling,a: production,P2,team-framework,triaged-framework

Internal issues: b/260398798 and b/260402304

Customer is reporting crashes in production with the following stack traces. They appear similar/related. There is no reproduction.

<details>

<summary> Stack trace for b/260398798 </summary>

```
Stable Signature - UnsupportedError at _getItemFromOffset at package:flutter/src/widgets/list_wheel_scroll_view.dart

at _getItemFromOffset (list_wheel_scroll_view.dart )
at _FixedExtentScrollPosition.itemIndex (list_wheel_scroll_view.dart:386 )
at _FixedExtentScrollPosition.copyWith (list_wheel_scroll_view.dart:409 )
at ScrollPosition.didUpdateScrollPositionBy (scroll_position.dart:914 )
at ScrollPosition.setPixels (scroll_position.dart:282 )
at ScrollPositionWithSingleContext.setPixels (scroll_position_with_single_context.dart:78 )
at ScrollPositionWithSingleContext.applyUserOffset (scroll_position_with_single_context.dart:122 )
at ScrollDragController.update (scroll_activity.dart:387 )
at ScrollableState._handleDragUpdate (scrollable.dart:674 )
at DragGestureRecognizer._checkUpdate.<anonymous closure> (monodrag.dart:483 )
at GestureRecognizer.invokeCallback (recognizer.dart:253 )
at DragGestureRecognizer._checkUpdate (monodrag.dart:483 )
at DragGestureRecognizer.handleEvent (monodrag.dart:330 )
at PointerRouter._dispatch (pointer_router.dart:98 )
at PointerRouter._dispatchEventToRoutes.<anonymous closure> (pointer_router.dart:143 )
at _LinkedHashMapMixin.forEach (compact_hash.dart:620 )
at PointerRouter._dispatchEventToRoutes (pointer_router.dart:141 )
at PointerRouter.route (pointer_router.dart:127 )
at GestureBinding.handleEvent (binding.dart:460 )
at GestureBinding.dispatchEvent (binding.dart:440 )
at RendererBinding.dispatchEvent (binding.dart:334 )
at GestureBinding._handlePointerEventImmediately (binding.dart:395 )
at GestureBinding.handlePointerEvent (binding.dart:357 )
at GestureBinding._flushPointerEventQueue (binding.dart:314 )
at GestureBinding._handlePointerDataPacket (binding.dart:295 )
at _rootRunUnary (zone.dart:1414 )
at _CustomZone.runUnary (zone.dart:1307 )
at _CustomZone.runUnaryGuarded (zone.dart:1216 )
at _invoke1 (hooks.dart:166 )
at PlatformDispatcher._dispatchPointerDataPacket (platform_dispatcher.dart:361 )
at _dispatchPointerDataPacket (hooks.dart:91 )
```

</details>

<details>

<summary> Stack trace for b/260402304 </summary>

```
UnsupportedError at _getItemFromOffset at package:flutter/src/widgets/list_wheel_scroll_view.dart-

at _getItemFromOffset (list_wheel_scroll_view.dart )
at _FixedExtentScrollPosition.itemIndex (list_wheel_scroll_view.dart:386 )
at FixedExtentScrollController.selectedItem (list_wheel_scroll_view.dart:251 )
at _RenderCupertinoPickerSemantics._handleScrollUpdate (picker.dart:475 )
at ChangeNotifier.notifyListeners (change_notifier.dart:354 )
at ChangeNotifier.notifyListeners (change_notifier.dart:354 )
at ScrollPosition.notifyListeners (scroll_position.dart:986 )
at ScrollPosition.setPixels (scroll_position.dart:281 )
at ScrollPositionWithSingleContext.setPixels (scroll_position_with_single_context.dart:79 )
at ScrollPositionWithSingleContext.applyUserOffset (scroll_position_with_single_context.dart:123 )
at ScrollDragController.update (scroll_activity.dart:397 )
at ScrollableState._handleDragUpdate (scrollable.dart:674 )
at DragGestureRecognizer._checkUpdate.<anonymous closure> (monodrag.dart:483 )
at GestureRecognizer.invokeCallback (recognizer.dart:253 )
at DragGestureRecognizer._checkUpdate (monodrag.dart:483 )
at DragGestureRecognizer.handleEvent (monodrag.dart:330 )
at PointerRouter._dispatch (pointer_router.dart:98 )
at PointerRouter._dispatchEventToRoutes.<anonymous closure> (pointer_router.dart:143 )
at _LinkedHashMapMixin.forEach (compact_hash.dart:617 )
at PointerRouter._dispatchEventToRoutes (pointer_router.dart:141 )
at PointerRouter.route (pointer_router.dart:127 )
at GestureBinding.handleEvent (binding.dart:460 )
at GestureBinding.dispatchEvent (binding.dart:440 )
at RendererBinding.dispatchEvent (binding.dart:333 )
at GestureBinding._handlePointerEventImmediately (binding.dart:395 )
at GestureBinding.handlePointerEvent (binding.dart:357 )
at GestureBinding._flushPointerEventQueue (binding.dart:314 )
at GestureBinding._handlePointerDataPacket (binding.dart:295 )
at _rootRunUnary (zone.dart:1414 )
at _CustomZone.runUnary (zone.dart:1307 )
at _CustomZone.runUnaryGuarded (zone.dart:1216 )
at _invoke1 (hooks.dart:166 )
at PlatformDispatcher._dispatchPointerDataPacket (platform_dispatcher.dart:343 )
at _dispatchPointerDataPacket (hooks.dart:91 )
```

</details>