Adds doc comments for FlutterVSyncClient and FlutterDisplayLink as well
as implementation notes in the -[FlutterDisplayLink onDisplayLink:]
callback.

Related PRs:
* flutter#186166
* flutter#186266

Adds doc comments for FlutterVSyncClient and FlutterDisplayLink as well
as implementation notes in the -[FlutterDisplayLink onDisplayLink:]
callback.

Related PRs:
* flutter#186166
* flutter#186266

Adds doc comments for FlutterVSyncClient and FlutterDisplayLink as well
as implementation notes in the -[FlutterDisplayLink onDisplayLink:]
callback.

Related PRs:
* flutter#186166
* flutter#186266

Roll Flutter from 707dbc0420a3 to 23f6f5853f50 (149 revisions)

flutter/flutter@707dbc0...23f6f58

2026-05-12 [email protected] Add 'cp: review' label to the manual cherrypick process (flutter/flutter#186158)
2026-05-12 [email protected] Roll Packages from 19ec8b8 to 93cbed6 (3 revisions) (flutter/flutter#186401)
2026-05-12 [email protected] Removes SDF option for macOS (always enabled) (flutter/flutter#186265)
2026-05-12 [email protected] docs: fix typos in flutter_tools comments (flutter/flutter#186321)
2026-05-12 [email protected] Pass XcodeBasedProject instead of String to functions in XcodeProjectInterpreter (flutter/flutter#186378)
2026-05-12 [email protected] Update iOS scenario app test goldens to match changes from flutter/flutter#182662 (flutter/flutter#186390)
2026-05-12 [email protected] Roll Skia from ad0aff15b9fa to 77a21bc723dc (2 revisions) (flutter/flutter#186396)
2026-05-12 [email protected] Migrate focus_node.unfocus.0.dart to use `RadioGroup` (flutter/flutter#183979)
2026-05-12 [email protected] Roll Skia from 91d3c1e730af to ad0aff15b9fa (7 revisions) (flutter/flutter#186391)
2026-05-12 [email protected] [Flutter GPU] Allow customizing the vertex layout on a RenderPipeline (flutter/flutter#186310)
2026-05-12 [email protected] Fix `EmbedderTest.CanRenderTextWithImpellerMetal` test breakage (flutter/flutter#186262)
2026-05-12 [email protected] Roll Fuchsia Linux SDK from rFhU-YPqdCRCtCz7b... to z7ICmPtn4hspu02zk... (flutter/flutter#186384)
2026-05-12 [email protected] [Impeller] GLES: lazily allocate texture mip levels on first per-level write (flutter/flutter#186302)
2026-05-12 [email protected] [Android] Propagate --enable-flutter-gpu Intent extra to engine args (flutter/flutter#186298)
2026-05-11 [email protected] [ci] update no-response workflow to also look for old label name in e… (flutter/flutter#186373)
2026-05-11 [email protected] [ImpellerC] Write a depfile when --shader-bundle is in use (flutter/flutter#186341)
2026-05-11 [email protected] docs: fix doubled-word typos in comments (flutter/flutter#186320)
2026-05-11 [email protected] Roll Skia from 32281401997e to 91d3c1e730af (4 revisions) (flutter/flutter#186368)
2026-05-11 [email protected] Show SwiftPM warnings right before iOS/macOS build (flutter/flutter#185984)
2026-05-11 [email protected] Convert rebuilding-flutter-tool script to dart (flutter/flutter#185089)
2026-05-11 [email protected] Use Xcode's LLDB (flutter/flutter#186273)
2026-05-11 [email protected] Remove `currentMainUri` from `generateMainDartWithPluginRegistrant` (flutter/flutter#185907)
2026-05-11 [email protected] Roll Skia from 2514f6b5f92b to 32281401997e (1 revision) (flutter/flutter#186349)
2026-05-11 [email protected] Roll Packages from 92552b1 to 19ec8b8 (4 revisions) (flutter/flutter#186350)
2026-05-11 [email protected] Check for absolute paths in skills.  (flutter/flutter#185632)
2026-05-11 [email protected] Roll Skia from 9fb7d2814642 to 2514f6b5f92b (1 revision) (flutter/flutter#186347)
2026-05-11 [email protected] Roll Skia from 8cafb209e836 to 9fb7d2814642 (4 revisions) (flutter/flutter#186335)
2026-05-10 [email protected] Roll Fuchsia Linux SDK from sOBiPJb0xznDBZlf5... to rFhU-YPqdCRCtCz7b... (flutter/flutter#186328)
2026-05-10 [email protected] Roll Skia from 05a03f99c74e to 8cafb209e836 (1 revision) (flutter/flutter#186315)
2026-05-10 [email protected] [Impeller] Vulkan: don't drop user-supplied viewport X, Y, and depth range (flutter/flutter#185886)
2026-05-09 [email protected] Update Fuchsia tests to subpackage their child components (flutter/flutter#186259)
2026-05-09 [email protected] Fix SelectableText crash with inline lambda contextMenuBuilder (flutter/flutter#184990)
2026-05-09 [email protected] Roll Fuchsia Linux SDK from 5_TnhTsHSqtCx37o6... to sOBiPJb0xznDBZlf5... (flutter/flutter#186289)
2026-05-09 [email protected] Roll Skia from dc78d4bd2efb to 05a03f99c74e (2 revisions) (flutter/flutter#186283)
2026-05-09 [email protected] Improve non rect platform view rendering  (flutter/flutter#182662)
2026-05-08 [email protected] Roll Skia from 31521f8508c7 to dc78d4bd2efb (1 revision) (flutter/flutter#186278)
2026-05-08 [email protected] Moves wide_gamut_macos to arm64 (flutter/flutter#186214)
2026-05-08 98614782+auto-submit[bot]@users.noreply.github.com Reverts "[iOS] Migrate VSyncClient to a pure Obj-C implementation (#186166)" (flutter/flutter#186266)
2026-05-08 [email protected] Roll Skia from a00db8749edb to 31521f8508c7 (2 revisions) (flutter/flutter#186264)
2026-05-08 [email protected] Optimize compatible `DrawDiffRoundRect` calls to use `DrawRoundRect` (flutter/flutter#186203)
2026-05-08 [email protected] [triage] Add Flutter GPU as a triage team (flutter/flutter#186263)
2026-05-08 [email protected] doc: Unified Check-Run User manual (flutter/flutter#186210)
2026-05-08 [email protected] Roll Skia from 5f7adf4403d6 to a00db8749edb (1 revision) (flutter/flutter#186257)
2026-05-08 [email protected] Roll Packages from 0411f1d to 92552b1 (1 revision) (flutter/flutter#186256)
2026-05-08 [email protected] Add logging to figure out jvm crashes for `hot_mode_tests` (flutter/flutter#186107)
2026-05-08 [email protected] Roll Skia from 926c09741ce2 to 5f7adf4403d6 (3 revisions) (flutter/flutter#186242)
...

…ink (flutter#186456)

Adds doc comments for FlutterVSyncClient and FlutterDisplayLink as well
as implementation notes in the `-[FlutterDisplayLink onDisplayLink:]`
callback.

No test changes since this is a documentation-only patch.

Related PRs:
* flutter#186166
* flutter#186266

## 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].
- [ ] I listed at least one issue that this PR fixes in the description
above.
- [X] I updated/added relevant documentation (doc comments with `///`).
- [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/docs/contributing/Tree-hygiene.md#ai-contribution-guidelines
[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
[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

…) (flutter#186935)

Migrates `FlutterVSyncClient` from a hybrid C++/Obj-C implementation to
a pure Objective-C implementation by removing C++ types from its
interface and implementation.

Previously, `FlutterVSyncClient` stored a C++
`flutter::VsyncWaiter::Callback` and used a temporary
`std::unique_ptr<flutter::FrameTimingsRecorder>` to propagate vsync
timestamps. This was redundant:

* `FlutterVSyncClient` allocated a temporary `FrameTimingsRecorder` and
recorded vsync times.
* It passed this to a C++ lambda wrapper.
* The lambda extracted the start/target times as seconds and passed them
to the Obj-C block callback.
* The temporary recorder was immediately discarded.
* `VsyncWaiterIOS` converted the seconds back to `fml::TimePoint`.
* `VsyncWaiter::FireCallback` allocated *another* `FrameTimingsRecorder`
and recorded the same times again.

We now:
* manage the callback as pure Obj-C block that accepts raw
`CFTimeInterval` (double seconds) directly from `CADisplayLink`.
* Remove the redundant `FrameTimingsRecorder` and C++ lambda wrapper.
* Rely solely on `VsyncWaiter::FireCallback` to handle the final
`FrameTimingsRecorder` creation and recording, which it already does.

This is a re-land of flutter#186166 which was reverted in flutter#186266. That patch
failed to correctly adjust the epoch of timestamps obtained from
CoreAnimation (which uses `mach_absolute_time` under the hood) to the
epoch used by the core engine, which is built on `fml::TimePoint`, which
uses `std::chrono::steady_clock`, which uses `mach_continuous_time`
under the hood, consistent with the C++ specification's of a continuous
clock. While these two clocks start roughly synchronized at boot,
`mach_absolute_time` pauses on device sleep, whereas
`mach_continuous_time` does not.

The iOS embedder now uses timings based on CoreAnimation throughout and
translates to `fml::TimePoint` only at the engine-embedder boundary.
This is consistent with embedders based on the embedder API, such as
macOS, which does this work in `-[FlutterEngine
viewControllerViewDidLoad]` using `FlutterTimeConverter`.

Added tests for frame rate snapping/fallback. No other test changes
because this introduces no semantic change and is covered by existing
tests recently added in: flutter#186457

Issue: flutter#112232

<!--
Thanks for filing a pull request!
Reviewers are typically assigned within a week of filing a request.
To learn more about code review, see our documentation on Tree Hygiene:
https://github.com/flutter/flutter/blob/main/docs/contributing/Tree-hygiene.md
-->

## 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 tested the crap outta this cause I really don't want to write
another post-mortem.
- [X] I updated/added relevant documentation (doc comments with `///`).
- [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/docs/contributing/Tree-hygiene.md#ai-contribution-guidelines
[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
[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

Roll Flutter from 707dbc0420a3 to 23f6f5853f50 (149 revisions)

flutter/flutter@707dbc0...23f6f58

2026-05-12 [email protected] Add 'cp: review' label to the manual cherrypick process (flutter/flutter#186158)
2026-05-12 [email protected] Roll Packages from 19ec8b861676 to 93cbed65f336 (3 revisions) (flutter/flutter#186401)
2026-05-12 [email protected] Removes SDF option for macOS (always enabled) (flutter/flutter#186265)
2026-05-12 [email protected] docs: fix typos in flutter_tools comments (flutter/flutter#186321)
2026-05-12 [email protected] Pass XcodeBasedProject instead of String to functions in XcodeProjectInterpreter (flutter/flutter#186378)
2026-05-12 [email protected] Update iOS scenario app test goldens to match changes from flutter/flutter#182662 (flutter/flutter#186390)
2026-05-12 [email protected] Roll Skia from ad0aff15b9fa to 77a21bc723dc (2 revisions) (flutter/flutter#186396)
2026-05-12 [email protected] Migrate focus_node.unfocus.0.dart to use `RadioGroup` (flutter/flutter#183979)
2026-05-12 [email protected] Roll Skia from 91d3c1e730af to ad0aff15b9fa (7 revisions) (flutter/flutter#186391)
2026-05-12 [email protected] [Flutter GPU] Allow customizing the vertex layout on a RenderPipeline (flutter/flutter#186310)
2026-05-12 [email protected] Fix `EmbedderTest.CanRenderTextWithImpellerMetal` test breakage (flutter/flutter#186262)
2026-05-12 [email protected] Roll Fuchsia Linux SDK from rFhU-YPqdCRCtCz7b... to z7ICmPtn4hspu02zk... (flutter/flutter#186384)
2026-05-12 [email protected] [Impeller] GLES: lazily allocate texture mip levels on first per-level write (flutter/flutter#186302)
2026-05-12 [email protected] [Android] Propagate --enable-flutter-gpu Intent extra to engine args (flutter/flutter#186298)
2026-05-11 [email protected] [ci] update no-response workflow to also look for old label name in e… (flutter/flutter#186373)
2026-05-11 [email protected] [ImpellerC] Write a depfile when --shader-bundle is in use (flutter/flutter#186341)
2026-05-11 [email protected] docs: fix doubled-word typos in comments (flutter/flutter#186320)
2026-05-11 [email protected] Roll Skia from 32281401997e to 91d3c1e730af (4 revisions) (flutter/flutter#186368)
2026-05-11 [email protected] Show SwiftPM warnings right before iOS/macOS build (flutter/flutter#185984)
2026-05-11 [email protected] Convert rebuilding-flutter-tool script to dart (flutter/flutter#185089)
2026-05-11 [email protected] Use Xcode's LLDB (flutter/flutter#186273)
2026-05-11 [email protected] Remove `currentMainUri` from `generateMainDartWithPluginRegistrant` (flutter/flutter#185907)
2026-05-11 [email protected] Roll Skia from 2514f6b5f92b to 32281401997e (1 revision) (flutter/flutter#186349)
2026-05-11 [email protected] Roll Packages from 92552b16bcc1 to 19ec8b861676 (4 revisions) (flutter/flutter#186350)
2026-05-11 [email protected] Check for absolute paths in skills.  (flutter/flutter#185632)
2026-05-11 [email protected] Roll Skia from 9fb7d2814642 to 2514f6b5f92b (1 revision) (flutter/flutter#186347)
2026-05-11 [email protected] Roll Skia from 8cafb209e836 to 9fb7d2814642 (4 revisions) (flutter/flutter#186335)
2026-05-10 [email protected] Roll Fuchsia Linux SDK from sOBiPJb0xznDBZlf5... to rFhU-YPqdCRCtCz7b... (flutter/flutter#186328)
2026-05-10 [email protected] Roll Skia from 05a03f99c74e to 8cafb209e836 (1 revision) (flutter/flutter#186315)
2026-05-10 [email protected] [Impeller] Vulkan: don't drop user-supplied viewport X, Y, and depth range (flutter/flutter#185886)
2026-05-09 [email protected] Update Fuchsia tests to subpackage their child components (flutter/flutter#186259)
2026-05-09 [email protected] Fix SelectableText crash with inline lambda contextMenuBuilder (flutter/flutter#184990)
2026-05-09 [email protected] Roll Fuchsia Linux SDK from 5_TnhTsHSqtCx37o6... to sOBiPJb0xznDBZlf5... (flutter/flutter#186289)
2026-05-09 [email protected] Roll Skia from dc78d4bd2efb to 05a03f99c74e (2 revisions) (flutter/flutter#186283)
2026-05-09 [email protected] Improve non rect platform view rendering  (flutter/flutter#182662)
2026-05-08 [email protected] Roll Skia from 31521f8508c7 to dc78d4bd2efb (1 revision) (flutter/flutter#186278)
2026-05-08 [email protected] Moves wide_gamut_macos to arm64 (flutter/flutter#186214)
2026-05-08 98614782+auto-submit[bot]@users.noreply.github.com Reverts "[iOS] Migrate VSyncClient to a pure Obj-C implementation (#186166)" (flutter/flutter#186266)
2026-05-08 [email protected] Roll Skia from a00db8749edb to 31521f8508c7 (2 revisions) (flutter/flutter#186264)
2026-05-08 [email protected] Optimize compatible `DrawDiffRoundRect` calls to use `DrawRoundRect` (flutter/flutter#186203)
2026-05-08 [email protected] [triage] Add Flutter GPU as a triage team (flutter/flutter#186263)
2026-05-08 [email protected] doc: Unified Check-Run User manual (flutter/flutter#186210)
2026-05-08 [email protected] Roll Skia from 5f7adf4403d6 to a00db8749edb (1 revision) (flutter/flutter#186257)
2026-05-08 [email protected] Roll Packages from cfdd1d3 to 92552b16bcc1 (1 revision) (flutter/flutter#186256)
2026-05-08 [email protected] Add logging to figure out jvm crashes for `hot_mode_tests` (flutter/flutter#186107)
2026-05-08 [email protected] Roll Skia from 926c09741ce2 to 5f7adf4403d6 (3 revisions) (flutter/flutter#186242)
...

…er#11700)

Roll Flutter from 707dbc0420a3 to 23f6f5853f50 (149 revisions)

flutter/flutter@707dbc0...23f6f58

2026-05-12 [email protected] Add 'cp: review' label to the manual cherrypick process (flutter/flutter#186158)
2026-05-12 [email protected] Roll Packages from 19ec8b8 to 93cbed6 (3 revisions) (flutter/flutter#186401)
2026-05-12 [email protected] Removes SDF option for macOS (always enabled) (flutter/flutter#186265)
2026-05-12 [email protected] docs: fix typos in flutter_tools comments (flutter/flutter#186321)
2026-05-12 [email protected] Pass XcodeBasedProject instead of String to functions in XcodeProjectInterpreter (flutter/flutter#186378)
2026-05-12 [email protected] Update iOS scenario app test goldens to match changes from flutter/flutter#182662 (flutter/flutter#186390)
2026-05-12 [email protected] Roll Skia from ad0aff15b9fa to 77a21bc723dc (2 revisions) (flutter/flutter#186396)
2026-05-12 [email protected] Migrate focus_node.unfocus.0.dart to use `RadioGroup` (flutter/flutter#183979)
2026-05-12 [email protected] Roll Skia from 91d3c1e730af to ad0aff15b9fa (7 revisions) (flutter/flutter#186391)
2026-05-12 [email protected] [Flutter GPU] Allow customizing the vertex layout on a RenderPipeline (flutter/flutter#186310)
2026-05-12 [email protected] Fix `EmbedderTest.CanRenderTextWithImpellerMetal` test breakage (flutter/flutter#186262)
2026-05-12 [email protected] Roll Fuchsia Linux SDK from rFhU-YPqdCRCtCz7b... to z7ICmPtn4hspu02zk... (flutter/flutter#186384)
2026-05-12 [email protected] [Impeller] GLES: lazily allocate texture mip levels on first per-level write (flutter/flutter#186302)
2026-05-12 [email protected] [Android] Propagate --enable-flutter-gpu Intent extra to engine args (flutter/flutter#186298)
2026-05-11 [email protected] [ci] update no-response workflow to also look for old label name in e… (flutter/flutter#186373)
2026-05-11 [email protected] [ImpellerC] Write a depfile when --shader-bundle is in use (flutter/flutter#186341)
2026-05-11 [email protected] docs: fix doubled-word typos in comments (flutter/flutter#186320)
2026-05-11 [email protected] Roll Skia from 32281401997e to 91d3c1e730af (4 revisions) (flutter/flutter#186368)
2026-05-11 [email protected] Show SwiftPM warnings right before iOS/macOS build (flutter/flutter#185984)
2026-05-11 [email protected] Convert rebuilding-flutter-tool script to dart (flutter/flutter#185089)
2026-05-11 [email protected] Use Xcode's LLDB (flutter/flutter#186273)
2026-05-11 [email protected] Remove `currentMainUri` from `generateMainDartWithPluginRegistrant` (flutter/flutter#185907)
2026-05-11 [email protected] Roll Skia from 2514f6b5f92b to 32281401997e (1 revision) (flutter/flutter#186349)
2026-05-11 [email protected] Roll Packages from 92552b1 to 19ec8b8 (4 revisions) (flutter/flutter#186350)
2026-05-11 [email protected] Check for absolute paths in skills.  (flutter/flutter#185632)
2026-05-11 [email protected] Roll Skia from 9fb7d2814642 to 2514f6b5f92b (1 revision) (flutter/flutter#186347)
2026-05-11 [email protected] Roll Skia from 8cafb209e836 to 9fb7d2814642 (4 revisions) (flutter/flutter#186335)
2026-05-10 [email protected] Roll Fuchsia Linux SDK from sOBiPJb0xznDBZlf5... to rFhU-YPqdCRCtCz7b... (flutter/flutter#186328)
2026-05-10 [email protected] Roll Skia from 05a03f99c74e to 8cafb209e836 (1 revision) (flutter/flutter#186315)
2026-05-10 [email protected] [Impeller] Vulkan: don't drop user-supplied viewport X, Y, and depth range (flutter/flutter#185886)
2026-05-09 [email protected] Update Fuchsia tests to subpackage their child components (flutter/flutter#186259)
2026-05-09 [email protected] Fix SelectableText crash with inline lambda contextMenuBuilder (flutter/flutter#184990)
2026-05-09 [email protected] Roll Fuchsia Linux SDK from 5_TnhTsHSqtCx37o6... to sOBiPJb0xznDBZlf5... (flutter/flutter#186289)
2026-05-09 [email protected] Roll Skia from dc78d4bd2efb to 05a03f99c74e (2 revisions) (flutter/flutter#186283)
2026-05-09 [email protected] Improve non rect platform view rendering  (flutter/flutter#182662)
2026-05-08 [email protected] Roll Skia from 31521f8508c7 to dc78d4bd2efb (1 revision) (flutter/flutter#186278)
2026-05-08 [email protected] Moves wide_gamut_macos to arm64 (flutter/flutter#186214)
2026-05-08 98614782+auto-submit[bot]@users.noreply.github.com Reverts "[iOS] Migrate VSyncClient to a pure Obj-C implementation (#186166)" (flutter/flutter#186266)
2026-05-08 [email protected] Roll Skia from a00db8749edb to 31521f8508c7 (2 revisions) (flutter/flutter#186264)
2026-05-08 [email protected] Optimize compatible `DrawDiffRoundRect` calls to use `DrawRoundRect` (flutter/flutter#186203)
2026-05-08 [email protected] [triage] Add Flutter GPU as a triage team (flutter/flutter#186263)
2026-05-08 [email protected] doc: Unified Check-Run User manual (flutter/flutter#186210)
2026-05-08 [email protected] Roll Skia from 5f7adf4403d6 to a00db8749edb (1 revision) (flutter/flutter#186257)
2026-05-08 [email protected] Roll Packages from 0411f1d to 92552b1 (1 revision) (flutter/flutter#186256)
2026-05-08 [email protected] Add logging to figure out jvm crashes for `hot_mode_tests` (flutter/flutter#186107)
2026-05-08 [email protected] Roll Skia from 926c09741ce2 to 5f7adf4403d6 (3 revisions) (flutter/flutter#186242)
...

…) (flutter#186935)

Migrates `FlutterVSyncClient` from a hybrid C++/Obj-C implementation to
a pure Objective-C implementation by removing C++ types from its
interface and implementation.

Previously, `FlutterVSyncClient` stored a C++
`flutter::VsyncWaiter::Callback` and used a temporary
`std::unique_ptr<flutter::FrameTimingsRecorder>` to propagate vsync
timestamps. This was redundant:

* `FlutterVSyncClient` allocated a temporary `FrameTimingsRecorder` and
recorded vsync times.
* It passed this to a C++ lambda wrapper.
* The lambda extracted the start/target times as seconds and passed them
to the Obj-C block callback.
* The temporary recorder was immediately discarded.
* `VsyncWaiterIOS` converted the seconds back to `fml::TimePoint`.
* `VsyncWaiter::FireCallback` allocated *another* `FrameTimingsRecorder`
and recorded the same times again.

We now:
* manage the callback as pure Obj-C block that accepts raw
`CFTimeInterval` (double seconds) directly from `CADisplayLink`.
* Remove the redundant `FrameTimingsRecorder` and C++ lambda wrapper.
* Rely solely on `VsyncWaiter::FireCallback` to handle the final
`FrameTimingsRecorder` creation and recording, which it already does.

This is a re-land of flutter#186166 which was reverted in flutter#186266. That patch
failed to correctly adjust the epoch of timestamps obtained from
CoreAnimation (which uses `mach_absolute_time` under the hood) to the
epoch used by the core engine, which is built on `fml::TimePoint`, which
uses `std::chrono::steady_clock`, which uses `mach_continuous_time`
under the hood, consistent with the C++ specification's of a continuous
clock. While these two clocks start roughly synchronized at boot,
`mach_absolute_time` pauses on device sleep, whereas
`mach_continuous_time` does not.

The iOS embedder now uses timings based on CoreAnimation throughout and
translates to `fml::TimePoint` only at the engine-embedder boundary.
This is consistent with embedders based on the embedder API, such as
macOS, which does this work in `-[FlutterEngine
viewControllerViewDidLoad]` using `FlutterTimeConverter`.

Added tests for frame rate snapping/fallback. No other test changes
because this introduces no semantic change and is covered by existing
tests recently added in: flutter#186457

Issue: flutter#112232

<!--
Thanks for filing a pull request!
Reviewers are typically assigned within a week of filing a request.
To learn more about code review, see our documentation on Tree Hygiene:
https://github.com/flutter/flutter/blob/main/docs/contributing/Tree-hygiene.md
-->

## 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 tested the crap outta this cause I really don't want to write
another post-mortem.
- [X] I updated/added relevant documentation (doc comments with `///`).
- [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/docs/contributing/Tree-hygiene.md#ai-contribution-guidelines
[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
[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