Improve error-recovery from unmatched braces.

Improve error-recovery from unmatched braces.

R=johnniwinther@google.com

Committed: https://code.google.com/p/dart/source/detail?r=35372

[ahe, 2014-04-24 12:43:34]

This is actually what I need for Try Dart :-)

I discovered, what I think is, a better way to recover from mismatched braces,
and dart2js can now compile this program:

foo() {[}
main() { print('Hello, world!'); }

[Johnni Winther, 2014-04-24 13:07:29]

lgtm

[ahe, 2014-04-24 13:08:32]

Thanks for looking out for tests, Luke!

https://codereview.chromium.org/251523002/diff/20001/dart/sdk/lib/_internal/c...
File dart/sdk/lib/_internal/compiler/implementation/warnings.dart (right):

https://codereview.chromium.org/251523002/diff/20001/dart/sdk/lib/_internal/c...
dart/sdk/lib/_internal/compiler/implementation/warnings.dart:1775: "main(){]}",
These three examples are tests. They are exercised by
dart/tests/compiler/dart2js/message_kind_test.dart which uses reflection to run
through all these messages looking for examples and make sure they produce the
expected error messages when analyzed.

Incidentally, message_kind_test reuses the compiler, something I plan to use in
Try Dart. Most of the examples in this file are analyzed in a few milliseconds
(and this is when the compiler is running in checked mode which is a bit slow).

[ahe, 2014-04-24 14:48:22]

Committed patchset #3 manually as r35372 (presubmit successful).