Extra error messages when compiling switch_expression_using_statement_syntax_error_test.dart for web

[stereotype441]

In https://dart-review.googlesource.com/c/sdk/+/293200 (Patterns parsing: recover when switch statement syntax used for switch expressions.), I've added a test tests/language/patterns/switch_expression_using_statement_syntax_error_test.dart to verify that error recovery does a good job of handling incorrect switch expression syntax.

When I ran pkg/test_runner/tool/update_static_error_tests.dart to automatically update the error expectations for that test, I was surprised to see some errors that are particular to the web platform:

f(x) => switch (x) {
//              ^
// [web] The type 'dynamic' is not exhaustively matched by the switch cases since it doesn't match 'Object()'.
  case 1: 'one';
  case 2: 'two';
  default: 'three';
  //     ^
  // [web] This couldn't be parsed.
};

main() {}

(I've left out the analyzer and cfe error expectations for brevity).

I'm not sure why the web platform is getting these extra errors, however after some manual experimenting, I'm guessing it may have something to do with the fact that my error recovery technique creates a wildcard pattern whose name token is default. I wonder if for some reason the web compiler gets confused by this, though it seems strange because the name token shouldn't have any effect on semantics.

[stereotype441]

Never mind, this was user error on my part. I had not rebuilt dart2js recently, so it was manifesting bugs that have since been fixed.