This uses optional new/const and `=` in named argument defaults.
All changes are automated, except for:
- utils/dartdevc/BUILD.gn: run DDC build scripts with --preview-dart-2
- pkg/dev_compiler/tool/patch_sdk.dart: add a TODO that Analyzer doesn't
supporting implicit const in libraries.dart
- pkg/dev_compiler/tool/input_sdk/libraries.dart: was not formatted due
to the aforementioned Analyzer bug
- tools/bots/test_matrix.json: run DDC sourcemap suite in Dart 2 mode
- pkg/pkg.status: skip pkg/dev_compiler if running in Dart 1 mode
Change-Id: I9b80ccba0c2cc7b66efc662a0b16562e3660aee3
Reviewed-on: https://dart-review.googlesource.com/60402
Commit-Queue: Jenny Messerly <jmesserly@google.com>
Reviewed-by: Bob Nystrom <rnystrom@google.com>
Jenny Messerly