[native_assets_builder] Recompile hook kernel if Dart changes

[dcharkes]

Addresses the remaining comments on #1750.

I'm unsure how to test the recompiling of the kernel file if Dart changes without writing a test that downloads a different Dart SDK.

[github-actions]

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// Copyright (c) 2024, the Dart project authors. Please see the AUTHORS file
// for details. All rights reserved. Use of this source code is governed by a
// BSD-style license that can be found in the LICENSE file.

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pkgs/ffigen/example/libclang-example/generated_bindings.dart
pkgs/ffigen/example/shared_bindings/generate.dart
pkgs/ffigen/example/shared_bindings/lib/generated/a_gen.dart
pkgs/ffigen/example/shared_bindings/lib/generated/a_shared_b_gen.dart
pkgs/ffigen/example/shared_bindings/lib/generated/base_gen.dart
pkgs/ffigen/example/simple/generated_bindings.dart
pkgs/ffigen/lib/src/header_parser/clang_bindings/clang_bindings.dart
pkgs/ffigen/test/collision_tests/expected_bindings/_expected_decl_decl_collision_bindings.dart
pkgs/ffigen/test/collision_tests/expected_bindings/_expected_decl_symbol_address_collision_bindings.dart
pkgs/ffigen/test/collision_tests/expected_bindings/_expected_decl_type_name_collision_bindings.dart
pkgs/ffigen/test/collision_tests/expected_bindings/_expected_reserved_keyword_collision_bindings.dart
pkgs/ffigen/test/header_parser_tests/expected_bindings/_expected_comment_markup_bindings.dart
pkgs/ffigen/test/header_parser_tests/expected_bindings/_expected_dart_handle_bindings.dart
pkgs/ffigen/test/header_parser_tests/expected_bindings/_expected_enum_int_mimic_bindings.dart
pkgs/ffigen/test/header_parser_tests/expected_bindings/_expected_forward_decl_bindings.dart
pkgs/ffigen/test/header_parser_tests/expected_bindings/_expected_functions_bindings.dart
pkgs/ffigen/test/header_parser_tests/expected_bindings/_expected_imported_types_bindings.dart
pkgs/ffigen/test/header_parser_tests/expected_bindings/_expected_native_func_typedef_bindings.dart
pkgs/ffigen/test/header_parser_tests/expected_bindings/_expected_opaque_dependencies_bindings.dart
pkgs/ffigen/test/header_parser_tests/expected_bindings/_expected_packed_structs_bindings.dart
pkgs/ffigen/test/header_parser_tests/expected_bindings/_expected_regress_384_bindings.dart
pkgs/ffigen/test/header_parser_tests/expected_bindings/_expected_sort_bindings.dart
pkgs/ffigen/test/header_parser_tests/expected_bindings/_expected_struct_fptr_fields_bindings.dart
pkgs/ffigen/test/header_parser_tests/expected_bindings/_expected_typedef_bindings.dart
pkgs/ffigen/test/header_parser_tests/expected_bindings/_expected_unions_bindings.dart
pkgs/ffigen/test/header_parser_tests/expected_bindings/_expected_varargs_bindings.dart
pkgs/ffigen/test/large_integration_tests/_expected_cjson_bindings.dart
pkgs/ffigen/test/large_integration_tests/_expected_libclang_bindings.dart
pkgs/ffigen/test/large_integration_tests/_expected_sqlite_bindings.dart
pkgs/ffigen/test/native_test/_expected_native_test_bindings.dart
pkgs/jni/lib/src/third_party/generated_bindings.dart
pkgs/jni/lib/src/third_party/global_env_extensions.dart
pkgs/jni/lib/src/third_party/jni_bindings_generated.dart
pkgs/jnigen/android_test_runner/lib/main.dart
pkgs/jnigen/example/in_app_java/lib/android_utils.dart
pkgs/jnigen/example/kotlin_plugin/example/lib/main.dart
pkgs/jnigen/example/kotlin_plugin/lib/kotlin_bindings.dart
pkgs/jnigen/example/kotlin_plugin/lib/kotlin_plugin.dart
pkgs/jnigen/example/pdfbox_plugin/lib/pdfbox_plugin.dart
pkgs/jnigen/example/pdfbox_plugin/lib/src/third_party/org/apache/pdfbox/pdmodel/PDDocument.dart
pkgs/jnigen/example/pdfbox_plugin/lib/src/third_party/org/apache/pdfbox/pdmodel/PDDocumentInformation.dart
pkgs/jnigen/example/pdfbox_plugin/lib/src/third_party/org/apache/pdfbox/pdmodel/_package.dart
pkgs/jnigen/example/pdfbox_plugin/lib/src/third_party/org/apache/pdfbox/text/PDFTextStripper.dart
pkgs/jnigen/example/pdfbox_plugin/lib/src/third_party/org/apache/pdfbox/text/_package.dart
pkgs/jnigen/lib/src/bindings/descriptor.dart
pkgs/jnigen/lib/src/bindings/printer.dart
pkgs/jnigen/lib/src/elements/elements.g.dart
pkgs/jnigen/test/jackson_core_test/third_party/bindings/com/fasterxml/jackson/core/_package.dart
pkgs/jnigen/test/type_path_test.dart
pkgs/jnigen/tool/command_runner.dart
pkgs/native_assets_builder/test_data/native_dynamic_linking/bin/native_dynamic_linking.dart
pkgs/objective_c/lib/src/ns_input_stream.dart
pkgs/swift2objc/lib/src/config.dart
pkgs/swift2objc/lib/src/generate_wrapper.dart
pkgs/swift2objc/lib/src/generator/_core/utils.dart
pkgs/swift2objc/lib/src/generator/generator.dart
pkgs/swift2objc/lib/src/parser/parsers/declaration_parsers/parse_initializer_declaration.dart
pkgs/swift2objc/lib/src/transformer/transformers/transform_globals.dart
pkgs/swift2objc/lib/src/transformer/transformers/transform_variable.dart

[coveralls]

coverage: 88.857% (+0.007%) from 88.85%
when pulling 82666be on hashing-comments
into e69c74d on main.

[mkustermann]

lgtm with comments

[dcharkes]

Thanks @mkustermann! 🙏