[DO NOT SUBMIT] web failure after formatting

[goderbauer]

Formatting lib/web_ui/lib/src/engine/renderer.dart with dartfmt causes compilation problems for the web engine:

FAILED: flutter_web_sdk/kernel/dart2js_platform.dill 
vpython3 ../../build/gn_run_binary.py ../../flutter/prebuilts/linux-x64/dart-sdk/bin/dart /b/s/w/ir/cache/builder/src/flutter/prebuilts/linux-x64/dart-sdk/bin/snapshots/kernel_worker.dart.snapshot --sound-null-safety --no-summary-only --null-environment --target dart2js --packages-file file:////b/s/w/ir/cache/builder/src/flutter/third_party/dart/.dart_tool/package_config.json --multi-root-scheme org-dartlang-sdk --multi-root file:////b/s/w/ir/cache/builder/src/out/wasm_release/flutter_web_sdk --libraries-file org-dartlang-sdk:///libraries.json --output /b/s/w/ir/cache/builder/src/out/wasm_release/flutter_web_sdk/kernel/dart2js_platform.dill --source dart:core --source dart:ui --source dart:ui_web --source dart:_engine --source dart:_skwasm_stub --source dart:_web_unicode --source dart:_web_locale_keymap --multi-root file:////b/s/w/ir/cache/builder/src/flutter/prebuilts/linux-x64
Command failed: ./../../flutter/prebuilts/linux-x64/dart-sdk/bin/dart /b/s/w/ir/cache/builder/src/flutter/prebuilts/linux-x64/dart-sdk/bin/snapshots/kernel_worker.dart.snapshot --sound-null-safety --no-summary-only --null-environment --target dart2js --packages-file file:////b/s/w/ir/cache/builder/src/flutter/third_party/dart/.dart_tool/package_config.json --multi-root-scheme org-dartlang-sdk --multi-root file:////b/s/w/ir/cache/builder/src/out/wasm_release/flutter_web_sdk --libraries-file org-dartlang-sdk:///libraries.json --output /b/s/w/ir/cache/builder/src/out/wasm_release/flutter_web_sdk/kernel/dart2js_platform.dill --source dart:core --source dart:ui --source dart:ui_web --source dart:_engine --source dart:_skwasm_stub --source dart:_web_unicode --source dart:_web_locale_keymap --multi-root file:////b/s/w/ir/cache/builder/src/flutter/prebuilts/linux-x64
exitCode: 15
org-dartlang-sdk:///lib/_engine/engine/renderer.dart:7:5: Error: 'if' can't be used as an identifier because it's a keyword.
Try renaming this to be an identifier that isn't a keyword.
    if (dart.library.html) 'package:ui/src/engine/skwasm/skwasm_stub.dart';
    ^^
org-dartlang-sdk:///lib/_engine/engine/renderer.dart:7:21: Error: Expected an identifier, but got '.'.
Try inserting an identifier before '.'.
    if (dart.library.html) 'package:ui/src/engine/skwasm/skwasm_stub.dart';
                    ^
org-dartlang-sdk:///lib/_engine/engine/renderer.dart:7:22: Error: Expected ')' before this.
    if (dart.library.html) 'package:ui/src/engine/skwasm/skwasm_stub.dart';
                     ^^^^
org-dartlang-sdk:///lib/_engine/engine/renderer.dart:7:28: Error: Expected '{' before this.
    if (dart.library.html) 'package:ui/src/engine/skwasm/skwasm_stub.dart';
                           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
org-dartlang-sdk:///lib/_engine/engine/renderer.dart:7:28: Error: Expected a declaration, but got ''package:ui/src/engine/skwasm/skwasm_stub.dart''.
    if (dart.library.html) 'package:ui/src/engine/skwasm/skwasm_stub.dart';
                           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
org-dartlang-sdk:///lib/_engine/engine/renderer.dart:7:75: Error: Unexpected token ';'.
    if (dart.library.html) 'package:ui/src/engine/skwasm/skwasm_stub.dart';
                                                                          ^
org-dartlang-sdk:///lib/_engine/engine/renderer.dart:7:9: Error: 'dart.library' can't be used as a type because 'dart' doesn't refer to an import prefix.
    if (dart.library.html) 'package:ui/src/engine/skwasm/skwasm_stub.dart';
        ^^^^^^^^^^^^
org-dartlang-sdk:///lib/_engine/engine/renderer.dart:7:9: Error: 'dart.library' can't be used as a type because 'dart' isn't defined.
    if (dart.library.html) 'package:ui/src/engine/skwasm/skwasm_stub.dart';
        ^^^^^^^^^^^^

[flutter-dashboard]

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[goderbauer]

@yjbanov or @ditman Any idea why the web engine fails building if lib/web_ui/lib/src/engine/renderer.dart is formatted with dartfmt as shown in this PR? The resulting formatting looks fine and legal to me. Is this file maybe post-processed in some way before compilation and that post-processing is failing with the new format? Any ideas?

[ditman]

Just for posterity, this was fixed by:

#57170

[ditman]

Answering @goderbauer's question about post-processing, there is indeed post processing in the flutter web engine that turns a bunch of import-based code in a big, fat, library that uses "parts" (😱), it's the:

• sdk_rewriter.dart