showModalBottomSheet creates ModalBottomSheetRoute that is never disposed.

[polina-c]

PR: #133595

Steps to repro:

1. Remove notDisposedAllowList added by the PR
2. Run the updated test library with 'flutter run '
3. Observe the test failure

flutter/packages/flutter/lib/src/material/bottom_sheet.dart

Line 1221 in 4022864

Future<T?> showModalBottomSheet<T>({

[chunhtai]

The ModalBottomSheetRoute will be disposed by Navigator after it is popped.
See

flutter/packages/flutter/lib/src/widgets/navigator.dart

Line 3118 in fc06fe6

route.dispose();

[polina-c]

Should it be documented for the method?

For some reason it does not happen in the test, marked by this PR: #133595
Is it issue of test or something is missing in the flutter framework code?

[chunhtai]

interesting, I think we will need to investigate further.