[scanner] Better recovery for missing end brace in string interpolation

Previous recovery resulted in an outline change and very bad performance
as a result (e.g. in the analyzer).

This takes an analyzer server benchmark from:

```
$ out/ReleaseX64/dart-sdk/bin/dart pkg/analysis_server/tool/benchmark_tools/big_chain_benchmark/lsp_typing_temporarily_missing_end_brace_in_string_interpolation.dart --types=ImportCycleExportChain --sizes=1024
[...]
==================================
size 1024 / CodeType.ImportCycleExportChain:
Initial analysis: 16.173549
Completion after change: 7.824299
Fully done after change: 24.515470
peak virtual memory size: 3941 MB
total program size (virtual): 3941 MB
peak resident set size ("high water mark"): 2125 MB
size of memory portions (rss): 2125 MB
==================================
```

to

```
==================================
size 1024 / CodeType.ImportCycleExportChain:
Initial analysis: 16.989549
Completion after change: 0.332792
Fully done after change: 0.333113
peak virtual memory size: 3817 MB
total program size (virtual): 3635 MB
peak resident set size ("high water mark"): 1983 MB
size of memory portions (rss): 1803 MB
==================================
```

Change-Id: I38478acbd9b0449c6962da7543aa4bd39b22d004
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/453341
Reviewed-by: Brian Wilkerson <brianwilkerson@google.com>
Reviewed-by: Johnni Winther <johnniwinther@google.com>
Commit-Queue: Jens Johansen <jensj@google.com>
19 files changed
tree: 358855f7ba3daefc6b8c15050d713fa552bc65f5
  1. .dart_tool/
  2. .github/
  3. benchmarks/
  4. build/
  5. docs/
  6. pkg/
  7. runtime/
  8. samples/
  9. sdk/
  10. tests/
  11. third_party/
  12. tools/
  13. utils/
  14. .clang-format
  15. .gitattributes
  16. .gitconfig
  17. .gitignore
  18. .gn
  19. .mailmap
  20. .style.yapf
  21. AUTHORS
  22. BUILD.gn
  23. CHANGELOG.md
  24. codereview.settings
  25. CONTRIBUTING.md
  26. DEPS
  27. LICENSE
  28. OWNERS
  29. PATENT_GRANT
  30. PRESUBMIT.py
  31. pubspec.yaml
  32. README.dart-sdk
  33. README.md
  34. sdk.code-workspace
  35. sdk_args.gni
  36. sdk_packages.yaml
  37. SECURITY.md
  38. WATCHLISTS
README.md

Dart

An approachable, portable, and productive language for high-quality apps on any platform

Dart is:

  • Approachable: Develop with a strongly typed programming language that is consistent, concise, and offers modern language features like null safety and patterns.

  • Portable: Compile to ARM, x64, or RISC-V machine code for mobile, desktop, and backend. Compile to JavaScript or WebAssembly for the web.

  • Productive: Make changes iteratively: use hot reload to see the result instantly in your running app. Diagnose app issues using DevTools.

Dart's flexible compiler technology lets you run Dart code in different ways, depending on your target platform and goals:

  • Dart Native: For programs targeting devices (mobile, desktop, server, and more), Dart Native includes both a Dart VM with JIT (just-in-time) compilation and an AOT (ahead-of-time) compiler for producing machine code.

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Dart platforms illustration

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See LICENSE and PATENT_GRANT.

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There are more documents in our repo at docs.

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