Run the mac_unopt sub-builds as standalone builders - #195868

…migration/phase0

The branch was 61 commits behind master. Merged rather than rebased: the
branch's commits are pushed and under review (PR flutter#196005).

Conflicts, resolved by hand:
- dev/bots/test.dart: master's flutter#195863 balances tool_tests_commands and
  web_tool_tests by duration through _selectWeightedToolTests (one
  durations file, dev/bots/tool_test_durations.json, for the three tool
  shards); the Bazel branches of the three shard runners now cover the
  paths it selects, as before over selectIndexOfTotalSubshard's.

Regenerated for master's rolls and renames:
- build_defs/repositories/deps.lock.bzl (gen_deps.dart): the Dart SDK roll
  to c9153304136a and its package revisions, the Fuchsia SDK and test
  scripts.
- build_defs/dart/pub.lock.bzl (gen_pub_lock.dart after `dart pub get` at
  the root and in lib/web_ui): the pubspec changes of master.
- engine/src/flutter/lib/ui/BUILD.bazel (gn_to_bazel): the GLES
  compositing unit test renamed to impeller_gles_without_surface_unittests.cc.
- engine/src/flutter/impeller/BUILD.bazel (gn_to_bazel): run_tests.py's
  Vulkan synchronization-validation list grew by the tests flutter#194989 fixed.
  `gn_to_bazel --check` is current.

Adjusted by hand for master's renames:
- dev/bots/BUILD.bazel and packages/flutter_tools/BUILD.bazel: the durations
  test is tool_test_durations_test over tool_test_durations.json and the
  test files of the commands, integration and web shards
  (`durations_shard_test_files`, was `integration_shard_test_files`).
- dev/bots/test/test_test.dart: the `_bazel` subshard test expects master's
  "Selecting subshard 1 of 3 (N of M tests, estimated weight W)".

Checked: gclient sync clean (Skia f96be51af95d, Dart c9153304136a);
gn_to_bazel 282/282 and --check current; bazel_tools 46/46; bazel_ci_test.py
23; pylint clean; Bazel analysis of //:framework_tests //:tool_tests
//:dart_tests //dev/bots:tests and of ci_host_debug_unopt (+tests),
android_debug, wasm_release, ci_android_release_arm64; `bazel test
//dev/bots:tests` green; dev/bots test_test.dart's Bazel tests green (its
`--dry-run prints every test` test depends on SHARD being set in the
environment, on master as here).

Note: master's flutter#195868 adds the mac_unopt builds as standalone bringup
builders under ci/builders/standalone/ (GN; the converter does not read
that directory). mac_unopt.json itself still carries --bazel.

The standalone builders added in flutter#195868 are passing in post-submit.
Remove bringup from them and delete the old mac_unopt orchestrator
builder and its config. Update docs that referenced mac_unopt.json.

(cherry picked from commit 84d0eb2)

The standalone builders added in flutter#195868 are passing in post-submit.
Remove bringup from them and delete the old mac_unopt orchestrator
builder and its config. Update docs that referenced mac_unopt.json.

(cherry picked from commit 84d0eb2)

The standalone builders added in flutter#195868 are passing, remove `bringup:
true` and delete the `Mac mac_unopt` builder.

The new builds ran on this PR, for example:

https://ci.chromium.org/ui/p/flutter/builders/try/Mac%20mac_host_release_arm64_licenses/1/overview

A few docs linked to mac_unopt.json or used it as an example, point them
instead to the `standalone/` configs.

Part of flutter#155041
Fixes flutter#186462

## Pre-launch Checklist

- [x] I read the [Contributor Guide] and followed the process outlined
there for submitting PRs.
- [x] I read the [AI contribution guidelines] and understand my
responsibilities, or I am not using AI tools.
- [x] I read the [Tree Hygiene] wiki page, which explains my
responsibilities.
- [x] I read and followed the [Flutter Style Guide], including [Features
we expect every widget to implement].
- [x] I signed the [CLA].
- [x] I listed at least one issue that this PR fixes in the description
above.
- [x] I updated/added relevant in-code documentation (doc comments with
`///`).
- [x] If this PR introduces a new feature or capability, I created and
linked a website documentation issue or PR in [flutter/website] (or
verified none is needed).
- [x] I added new tests to check the change I am making, or this PR is
[test-exempt].
- [x] I followed the [breaking change policy] and added [Data Driven
Fixes] where supported.
- [x] All existing and new tests are passing.

If you need help, consider asking for advice on the #hackers-new channel
on [Discord].

If this change needs to override an active code freeze, provide a
comment explaining why. The code freeze workflow can be overridden by
code reviewers. See pinned issues for any active code freezes with
guidance.

**Note**: The Flutter team is currently trialing the use of [Gemini Code
Assist for
GitHub](https://developers.google.com/gemini-code-assist/docs/review-github-code).
Comments from the `gemini-code-assist` bot should not be taken as
authoritative feedback from the Flutter team. If you find its comments
useful you can update your code accordingly, but if you are unsure or
disagree with the feedback, please feel free to wait for a Flutter team
member's review for guidance on which automated comments should be
addressed.

<!-- Links -->
[Contributor Guide]:
https://github.com/flutter/flutter/blob/main/docs/contributing/Tree-hygiene.md#overview
[AI contribution guidelines]:
https://github.com/flutter/flutter/blob/main/CONTRIBUTING.ai.md
[Tree Hygiene]:
https://github.com/flutter/flutter/blob/main/docs/contributing/Tree-hygiene.md
[test-exempt]:
https://github.com/flutter/flutter/blob/main/docs/contributing/Tree-hygiene.md#tests
[Flutter Style Guide]:
https://github.com/flutter/flutter/blob/main/docs/contributing/Style-guide-for-Flutter-repo.md
[Features we expect every widget to implement]:
https://github.com/flutter/flutter/blob/main/docs/contributing/Style-guide-for-Flutter-repo.md#features-we-expect-every-widget-to-implement
[CLA]: https://cla.developers.google.com/
[flutter/tests]: https://github.com/flutter/tests
[flutter/website]: https://github.com/flutter/website
[breaking change policy]:
https://github.com/flutter/flutter/blob/main/docs/contributing/Tree-hygiene.md#handling-breaking-changes
[Discord]:
https://github.com/flutter/flutter/blob/main/docs/contributing/Chat.md
[Data Driven Fixes]:
https://github.com/flutter/flutter/blob/main/docs/contributing/Data-driven-Fixes.md

This pull request is created by [automatic cherry pick workflow](https://github.com/flutter/flutter/blob/main/docs/releases/Flutter-Cherrypick-Process.md#automatically-creates-a-cherry-pick-request)
Please fill in the form below, and a flutter domain expert will evaluate this cherry pick request.

### Issue Link:
#186462

2 PRs: #195868 and #196027

### Impact Description:
Release builders should match the master branch configs. Without this change, the beta release branch will try to run the old builder names and fail because the infra config is missing.

### Changelog Description:
N/A - CI test-only change

### Workaround:
N/A

### Risk:
What is the risk level of this cherry-pick?

### Test Coverage:
Are you confident that your fix is well-tested by automated tests?

### Validation Steps:
Release PRs should not complain about missing builders.

…'s builds were; the converter reads ci/builders/standalone/*.json

Master's flutter#195868 and flutter#196027 moved mac_unopt.json's eight builds into
one-build files under ci/builders/standalone/ (the engine_v2/builder
recipe's form: name, gn, ninja and tests at the top of the file) and
removed the mac_unopt builder, so 523's merge took the deletion and the
Mac test drones -- host_{debug,profile,release}_arm64_tests,
host_release_arm64_licenses, mac_release_arm64_tests,
host_debug_unopt_arm64, ios_debug_unopt_sim_arm64 and its extension-safe
twin -- ran GN again in 523's presubmit (and ios_debug_unopt_sim_arm64
failed a timing test of the GN-built embedder unit tests,
testViewWillTransitionToSize_DoesDelayEngineCallIfNonZeroDuration, three
times; it passes on master's postsubmit and failed another PR the same way
this morning).

- tools/gn_to_bazel: withStandaloneBuilds (builders.dart) reads a
  standalone file's build out of it -- BuildConfigLoader reads such a file
  as a builder file with no builds -- as a builder file of that one build
  under the loader's key, so the host's prefix, the configurations, the
  installs, the suites, builds.json and the --bazel checks cover them as
  they cover linux_*.json and mac_*.json; gn_to_bazel.dart applies it.
  Test added. The GN-only standalone builds (linux_benchmarks,
  linux_clangd, mac_clangd) get configurations like any other GN build's;
  linux_license's --enable-minimal-linux has none.
- ci/builders/standalone/mac_*.json (the eight): --no-rbe for --rbe,
  --bazel appended, download_bazelisk among the gclient variables (use_rbe
  stays true: the Mac's reclient and the Linux clang for the wraps), and
  the licenses build's unit-test step as run_tests.py --type binaries, as
  517 had it in mac_unopt.json (the converter refuses the executable
  step). mac_clangd.json stays GN.
- ci/builders/BUILD.bazel, configs.bazelrc, build/bazel/builds.json
  regenerated: the eight Mac configurations and installs are back, plus
  the GN-only standalone builds' configurations. ci.md's builder list.

Converter 282+1 tests, --check current; engine_build_configs 84;
bazel_ci_test 23; buildifier clean.

Swift Testing runs a suite's tests in parallel.
`testStaticLogInfoDoesNotEvaluateMessageBelowLogLevel` sets the global
`Logger.logLevel` to `.warning` and expects no output, while
`testConcurrentLoggingAndLevelMutation` flips it to `.info` and logs.
When they overlap the first one fails. Put both in a nested
`@Suite(.serialized)`.

This is the top cause of test-step retries on the standalone Mac
mac_host_*_arm64_tests builders from flutter#195868, and each retry reruns the
whole 7–27 minute step.

Fixes flutter#194776

## Pre-launch Checklist

- [x] I read the [Contributor Guide] and followed the process outlined
there for submitting PRs.
- [x] I read the [AI contribution guidelines] and understand my
responsibilities, or I am not using AI tools.
- [x] I read the [Tree Hygiene] wiki page, which explains my
responsibilities.
- [x] I read and followed the [Flutter Style Guide], including [Features
we expect every widget to implement].
- [x] I signed the [CLA].
- [x] I listed at least one issue that this PR fixes in the description
above.
- [x] I updated/added relevant in-code documentation (doc comments with
`///`).
- [x] If this PR introduces a new feature or capability, I created and
linked a website documentation issue or PR in [flutter/website] (or
verified none is needed).
- [x] I added new tests to check the change I am making, or this PR is
[test-exempt].
- [x] I followed the [breaking change policy] and added [Data Driven
Fixes] where supported.
- [x] All existing and new tests are passing.

If you need help, consider asking for advice on the #hackers-new channel
on [Discord].

If this change needs to override an active code freeze, provide a
comment explaining why. The code freeze workflow can be overridden by
code reviewers. See pinned issues for any active code freezes with
guidance.

**Note**: The Flutter team is currently trialing the use of [Gemini Code
Assist for
GitHub](https://developers.google.com/gemini-code-assist/docs/review-github-code).
Comments from the `gemini-code-assist` bot should not be taken as
authoritative feedback from the Flutter team. If you find its comments
useful you can update your code accordingly, but if you are unsure or
disagree with the feedback, please feel free to wait for a Flutter team
member's review for guidance on which automated comments should be
addressed.

<!-- Links -->
[Contributor Guide]:
https://github.com/flutter/flutter/blob/main/docs/contributing/Tree-hygiene.md#overview
[AI contribution guidelines]:
https://github.com/flutter/flutter/blob/main/CONTRIBUTING.ai.md
[Tree Hygiene]:
https://github.com/flutter/flutter/blob/main/docs/contributing/Tree-hygiene.md
[test-exempt]:
https://github.com/flutter/flutter/blob/main/docs/contributing/Tree-hygiene.md#tests
[Flutter Style Guide]:
https://github.com/flutter/flutter/blob/main/docs/contributing/Style-guide-for-Flutter-repo.md
[Features we expect every widget to implement]:
https://github.com/flutter/flutter/blob/main/docs/contributing/Style-guide-for-Flutter-repo.md#features-we-expect-every-widget-to-implement
[CLA]: https://cla.developers.google.com/
[flutter/tests]: https://github.com/flutter/tests
[flutter/website]: https://github.com/flutter/website
[breaking change policy]:
https://github.com/flutter/flutter/blob/main/docs/contributing/Tree-hygiene.md#handling-breaking-changes
[Discord]:
https://github.com/flutter/flutter/blob/main/docs/contributing/Chat.md
[Data Driven Fixes]:
https://github.com/flutter/flutter/blob/main/docs/contributing/Data-driven-Fixes.md

…'s builds were; the converter reads ci/builders/standalone/*.json

Master's flutter#195868 and flutter#196027 moved mac_unopt.json's eight builds into
one-build files under ci/builders/standalone/ (the engine_v2/builder
recipe's form: name, gn, ninja and tests at the top of the file) and
removed the mac_unopt builder, so 523's merge took the deletion and the
Mac test drones -- host_{debug,profile,release}_arm64_tests,
host_release_arm64_licenses, mac_release_arm64_tests,
host_debug_unopt_arm64, ios_debug_unopt_sim_arm64 and its extension-safe
twin -- ran GN again in 523's presubmit (and ios_debug_unopt_sim_arm64
failed a timing test of the GN-built embedder unit tests,
testViewWillTransitionToSize_DoesDelayEngineCallIfNonZeroDuration, three
times; it passes on master's postsubmit and failed another PR the same way
this morning).

- tools/gn_to_bazel: withStandaloneBuilds (builders.dart) reads a
  standalone file's build out of it -- BuildConfigLoader reads such a file
  as a builder file with no builds -- as a builder file of that one build
  under the loader's key, so the host's prefix, the configurations, the
  installs, the suites, builds.json and the --bazel checks cover them as
  they cover linux_*.json and mac_*.json; gn_to_bazel.dart applies it.
  Test added. The GN-only standalone builds (linux_benchmarks,
  linux_clangd, mac_clangd) get configurations like any other GN build's;
  linux_license's --enable-minimal-linux has none.
- ci/builders/standalone/mac_*.json (the eight): --no-rbe for --rbe,
  --bazel appended, download_bazelisk among the gclient variables (use_rbe
  stays true: the Mac's reclient and the Linux clang for the wraps), and
  the licenses build's unit-test step as run_tests.py --type binaries, as
  517 had it in mac_unopt.json (the converter refuses the executable
  step). mac_clangd.json stays GN.
- ci/builders/BUILD.bazel, configs.bazelrc, build/bazel/builds.json
  regenerated: the eight Mac configurations and installs are back, plus
  the GN-only standalone builds' configurations. ci.md's builder list.

Converter 282+1 tests, --check current; engine_build_configs 84;
bazel_ci_test 23; buildifier clean.