Dart -> Engine roll blocked on // @dart=2.9 in a couple Fuchsia test files #113943
Description
Starting in flutter/engine#36946 in build https://ci.chromium.org/ui/p/flutter/builders/try/Linux%20Fuchsia/56615/overview.
FAILED: gen/flutter/shell/platform/fuchsia/flutter/tests/integration/touch-input/touch-input-view/__untraced_dart_kernel__/component.dil gen/flutter/shell/platform/fuchsia/flutter/tests/integration/touch-input/touch-input-view/touch-input-view_kernel.dilpmanifest gen/flutter/shell/platform/fuchsia/flutter/tests/integration/touch-input/touch-input-view/touch-input-view_kernel.dilpmanifest.dilplist gen/flutter/shell/platform/fuchsia/flutter/tests/integration/touch-input/touch-input-view/touch-input-view_kernel.dilpmanifest.frameworkversion
vpython3 ../../flutter/tools/fuchsia/depfile_path_to_relative.py --depfile=gen/flutter/shell/platform/fuchsia/flutter/tests/integration/touch-input/touch-input-view/__untraced_dart_kernel__/component.dil.d -- clang_x64/dart-tools/gen_kernel --component-name touch-input-view --verbosity=warning --no-sound-null-safety --target flutter_runner --platform flutter_runner_patched_sdk/platform_strong.dill --filesystem-scheme fuchsia-source --filesystem-root /b/s/w/ir/cache/builder/src/ --packages fuchsia-source:///out/fuchsia_debug_x64/gen/flutter/shell/platform/fuchsia/flutter/tests/integration/touch-input/touch-input-view/component_dart_package_package_config.json --depfile gen/flutter/shell/platform/fuchsia/flutter/tests/integration/touch-input/touch-input-view/__untraced_dart_kernel__/component.dil.d --output gen/flutter/shell/platform/fuchsia/flutter/tests/integration/touch-input/touch-input-view/__untraced_dart_kernel__/component.dil --split-output-by-packages --manifest gen/flutter/shell/platform/fuchsia/flutter/tests/integration/touch-input/touch-input-view/touch-input-view_kernel.dilpmanifest --embed-sources --no-link-platform package:touch-input-view/touch-input-view.dart
fuchsia-source:///third_party/dart/third_party/pkg/args/lib/src/arg_parser_exception.dart:12:22: Error: The 'super-parameters' language feature is disabled for this library.
Try removing the package language version or setting the language version to 2.17 or higher.
ArgParserException(super.message, [Iterable<String>? commands])
^^^^^
[8895/9111] ACTION //flutter/shell/platform/fuchsia/flutter/tests/integration/embedder/parent-view:parent-view_kernel_gen_file(//build/toolchain/fuchsia:fuchsia)
FAILED: gen/flutter/shell/platform/fuchsia/flutter/tests/integration/embedder/parent-view/__untraced_dart_kernel__/component.dil gen/flutter/shell/platform/fuchsia/flutter/tests/integration/embedder/parent-view/parent-view_kernel.dilpmanifest gen/flutter/shell/platform/fuchsia/flutter/tests/integration/embedder/parent-view/parent-view_kernel.dilpmanifest.dilplist gen/flutter/shell/platform/fuchsia/flutter/tests/integration/embedder/parent-view/parent-view_kernel.dilpmanifest.frameworkversion
vpython3 ../../flutter/tools/fuchsia/depfile_path_to_relative.py --depfile=gen/flutter/shell/platform/fuchsia/flutter/tests/integration/embedder/parent-view/__untraced_dart_kernel__/component.dil.d -- clang_x64/dart-tools/gen_kernel --component-name parent-view --verbosity=warning --no-sound-null-safety --target flutter_runner --platform flutter_runner_patched_sdk/platform_strong.dill --filesystem-scheme fuchsia-source --filesystem-root /b/s/w/ir/cache/builder/src/ --packages fuchsia-source:///out/fuchsia_debug_x64/gen/flutter/shell/platform/fuchsia/flutter/tests/integration/embedder/parent-view/component_dart_package_package_config.json --depfile gen/flutter/shell/platform/fuchsia/flutter/tests/integration/embedder/parent-view/__untraced_dart_kernel__/component.dil.d --output gen/flutter/shell/platform/fuchsia/flutter/tests/integration/embedder/parent-view/__untraced_dart_kernel__/component.dil --split-output-by-packages --manifest gen/flutter/shell/platform/fuchsia/flutter/tests/integration/embedder/parent-view/parent-view_kernel.dilpmanifest --embed-sources --no-link-platform package:parent-view/parent_view.dart
fuchsia-source:///third_party/dart/third_party/pkg/args/lib/src/arg_parser_exception.dart:12:22: Error: The 'super-parameters' language feature is disabled for this library.
Try removing the package language version or setting the language version to 2.17 or higher.
ArgParserException(super.message, [Iterable<String>? commands])
^^^^^
The flagged files say // @dart=2.9 at the top.
https://github.com/flutter/engine/blob/main/shell/platform/fuchsia/flutter/tests/integration/text-input/text-input-view/lib/text_input_view.dart
https://github.com/flutter/engine/blob/main/shell/platform/fuchsia/flutter/tests/integration/touch-input/touch-input-view/lib/touch-input-view.dart
The second file points at issue https://fxbug.dev/84961, which indicates that the files might not yet have been migrated for null-safety.