Cherrypicks for 1.12.13+hotfix.9 (#17306)


* Update Dart revision to 2.7.2.  https://docs.google.com/document/d/1qTFdBeMaIa6wvvdyrSRtYDpgotxuz9gpBshgqrQsh1w/edit?hl=en#

* CP of #16948 - remove duplicate dependency on the Dart language model

* remove duplicate dark SDK version from DEPS

* pin flutter framework repo to v1.12.13-hotfixes branch

* update licenses_third_party golden - signature update only, no licenses changed
3 files changed
tree: c3ecf483eb4f758425364116469030be5833d2bf
  1. .github/
  2. assets/
  3. benchmarking/
  4. build/
  5. ci/
  6. common/
  7. docs/
  8. examples/
  9. flow/
  10. flutter_frontend_server/
  11. fml/
  12. lib/
  13. runtime/
  14. shell/
  15. sky/
  16. testing/
  17. third_party/
  18. tools/
  19. vulkan/
  20. web_sdk/
  21. .cirrus.yml
  22. .clang-format
  23. .gitattributes
  24. .gitignore
  25. analysis_options.yaml
  26. AUTHORS
  27. BUILD.gn
  28. CONTRIBUTING.md
  29. DEPS
  30. Doxyfile
  31. LICENSE
  32. README.md
  33. recipe_changelog.md
README.md

Flutter Engine

Build Status - Cirrus

Flutter is Google's mobile app SDK for crafting high-quality native interfaces in record time. Flutter works with existing code, is used by developers and organizations around the world, and is free and open source.

The Flutter Engine is a portable runtime for hosting Flutter applications. It implements Flutter's core libraries, including animation and graphics, file and network I/O, accessibility support, plugin architecture, and a Dart runtime and compile toolchain. Most developers will interact with Flutter via the Flutter Framework, which provides a modern, reactive framework, and a rich set of platform, layout and foundation widgets.

If you are new to Flutter, then you will find more general information on the Flutter project, including tutorials and samples, on our Web site at Flutter.dev. For specific information about Flutter's APIs, consider our API reference which can be found at the docs.flutter.dev.

Flutter is a fully open source project, and we welcome contributions. Information on how to get started can be found at our contributor guide.