_⚠️ Landing this is blocked until: 1)
https://critique.corp.google.com/cl/781275353 lands and 2) google3 is
updated to add the new feature flag introduced in
flutter#171903

Currently, google3's `Google3Features` extends `FeatureFlags`. As a
result, google3 automatically gets the same feature flag values as in
Flutter.

This makes Flutter's feature flag values abstract, thereby requiring
that google3's `Google3Features` must explicitly set each feature flag's
value.

Discussion that motivated this change:
flutter#171797
Internal CL: https://critique.corp.google.com/cl/781275353
Part of: flutter#167668

## Pre-launch Checklist

- [x] I read the [Contributor Guide] and followed the process outlined
there for submitting PRs.
- [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 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].

<!-- Links -->
[Contributor Guide]:
https://github.com/flutter/flutter/blob/main/docs/contributing/Tree-hygiene.md#overview
[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#171933)

Roll Flutter from 43657f3baa17 to 35f197f1e5f5 (39 revisions)

flutter/flutter@43657f3...35f197f

2025-07-12 [email protected] Roll Fuchsia Linux SDK from 8aoEy1hp2a9HI1pt-... to xQlbHCUI33kDvkew8... (flutter/flutter#172060)
2025-07-12 [email protected] Add RSuperellipse support to Web (global cache) (flutter/flutter#171489)
2025-07-12 [email protected] Fix grammar: Change 'A' to 'An' before IOSSystemContextMenuItemData (flutter/flutter#172019)
2025-07-11 [email protected] Manual roll Dart to b21dca1b89ff (flutter/flutter#172038)
2025-07-11 [email protected] Roll Skia from 2ea2ba09ef85 to 92354f64e37f (1 revision) (flutter/flutter#172039)
2025-07-11 [email protected] Fix CheckedPopupMenuItem semantics to use menuItemCheckbox role with checked state (flutter/flutter#171749)
2025-07-11 [email protected] adds gemini.md to `engine` and `licenses_cpp` (flutter/flutter#172022)
2025-07-11 [email protected] [Web] Implement disabling interactive selection (flutter/flutter#171935)
2025-07-11 [email protected] [tool] Make google3 have to override feature flags (flutter/flutter#171933)
2025-07-11 [email protected] License cpp 710 (flutter/flutter#171989)
2025-07-11 [email protected] add content description to tooltip-only nodes for android (flutter/flutter#171541)
2025-07-11 [email protected] [Web a11y]Update table cell to use LabelRepresentation.sizedSpan  (flutter/flutter#172013)
2025-07-11 [email protected] [ Tool ] Enable `omit_obvious_*_types` and `specify_nonobvious_*_types` lints (flutter/flutter#172018)
2025-07-11 [email protected] Add SemanticsLabelBuilder for Accessible Label Concatenation (flutter/flutter#171683)
2025-07-11 [email protected] Run tests on either macOS 14 or 15 (flutter/flutter#171076)
2025-07-11 [email protected] Roll Skia from db1a5550c848 to 2ea2ba09ef85 (1 revision) (flutter/flutter#172017)
2025-07-11 [email protected] [Cupertino] Make some widgets no longer use RSuperellipse (flutter/flutter#171830)
2025-07-11 [email protected] Detach the resource context from the IO thread only if the shell's IO manager is no longer being used by any other spawned shells (flutter/flutter#171554)
2025-07-11 [email protected] Started querying the app state for the gpu disabled sync switch (flutter/flutter#171785)
2025-07-11 [email protected] License_cpp 7/02 (flutter/flutter#171558)
2025-07-11 [email protected] [web] Refactor clipboard. (flutter/flutter#171427)
2025-07-11 [email protected] Require 64-bit Windows (flutter/flutter#171925)
2025-07-11 [email protected] Run hot_reload_with_asset_web_test.dart on Mac/Windows (flutter/flutter#171280)
2025-07-11 [email protected] Roll Skia from da7e3eae7c2b to db1a5550c848 (2 revisions) (flutter/flutter#171999)
2025-07-11 [email protected] Roll Skia from 26571c3b1771 to da7e3eae7c2b (2 revisions) (flutter/flutter#171997)
2025-07-11 [email protected] Roll Skia from 34a40032ff0a to 26571c3b1771 (1 revision) (flutter/flutter#171995)
2025-07-11 [email protected] Roll Fuchsia Linux SDK from lO64ePNEGrGzs-MFC... to 8aoEy1hp2a9HI1pt-... (flutter/flutter#171993)
2025-07-10 [email protected] Remove redundant ThemeData(useMaterial3: true) from tests (flutter/flutter#171569)
2025-07-10 [email protected] [Android 16] Updated linux_android_emu to a 36 AVD in framework CI (flutter/flutter#169121)
2025-07-10 [email protected] [iOS] Add Live Text option to system context menu (flutter/flutter#170969)
2025-07-10 [email protected] Roll Skia from dc3da09ca905 to 34a40032ff0a (1 revision) (flutter/flutter#171982)
2025-07-10 [email protected] feat: Expose FocusNode of FocusTraversalGroup (flutter/flutter#171979)
2025-07-10 [email protected] `CupertinoDatePicker` and `CupertinoTimerPicker` new onChanged behavior (flutter/flutter#170793)
2025-07-10 [email protected] Manual roll Dart SDK from 8d69b07b9d9d to 07ea3aaaadf0 (32 revisions) (flutter/flutter#171969)
2025-07-10 [email protected] Style: Rename pageBuilder with builder in showCupertinoSheet (flutter/flutter#170625)
2025-07-10 [email protected] Roll Skia from bdb8bfcde7f3 to dc3da09ca905 (3 revisions) (flutter/flutter#171971)
2025-07-10 [email protected] Feat: Add foreground color for cupertino button (flutter/flutter#170898)
2025-07-10 [email protected] Roll Skia from 0fef076beec3 to bdb8bfcde7f3 (34 revisions) (flutter/flutter#171964)
2025-07-10 [email protected] Run stateless_stateful_hot_reload_web_test.dart on Mac/Windows (flutter/flutter#171283)

If this roll has caused a breakage, revert this CL and stop the roller
using the controls here:
https://autoroll.skia.org/r/flutter-packages
Please CC [email protected],[email protected] on the revert to ensure that a human
is aware of the problem.

...

This relands #168437. The google3
fixes were landed in: #171547,
https://critique.corp.google.com/cl/781275353,
#171933.

This PR is split into two commits:

1. d625379, code from
#168437 without any changes
2. f35d29e, updates the PR to omit
obvious types.

Original PR description:

## Motivation

We'd like to let users opt-in to experimental features so that they can
give early feedback while we iterate on the feature. For example:

Example feature flags:

1. Android sensitive content:
#158473. When enabled, Flutter
will tell Android when the view contains sensitive content like a
password.
3. Desktop multi-window. When enabled, Flutter will use child windows to
allow things like a context menu to "escape" outside of the current
window.

### Use case

Users will be able to turn on features by:

* **Option 1**: Run `flutter config --enable-my-feature`. This enables
the feature for all projects on the machine
* **Option 2**: Add `enable-my-feature: true` in their `pubspec.yaml`,
under the `flutter` section. This would enable the for a single project
on the machine.

Turning on a feature affects _both_ development-time (`flutter run`) and
deployment-time (`flutter build x`). For example, I can `flutter build
windows` to create an `.exe` with multi-window features enabled.

## How this works

This adds a new
[`runtimeId`](https://github.com/flutter/flutter/pull/168437/files#diff-0ded384225f19a4c34d43c7c11f7cb084ff3db947cfa82d8d52fc94c112bb2a7R243-R247)
property to the tool's `Feature` class. If a feature is on and has a
`runtimeId`, its `runtimeId` will be [stamped into the Dart application
as a Dart
define](https://github.com/flutter/flutter/pull/168437/files#diff-bd662448bdc2e6f50e47cd3b20b22b41a828561bce65cb4d54ea4f5011cc604eR293-R327).
The framework uses this Dart define to [determine which features are
enabled](https://github.com/flutter/flutter/pull/168437/files#diff-c8dbd5cd3103bc5be53c4ac5be8bdb9bf73e10cd5d8e4ac34e737fd1f8602d45).

### Multi-window example

#168697 shows how this new
feature flag system can be used to add a multi-window feature flag:

1. It adds a new [multi-window
feature](https://github.com/flutter/flutter/pull/168697/files#diff-0ded384225f19a4c34d43c7c11f7cb084ff3db947cfa82d8d52fc94c112bb2a7R189-R198)
to the Flutter tool. This can be turned on using `flutter config
--enable-multi-window` or by putting `enable-multi-window: true` in an
app's .pubspec, under the `flutter` section.
2. It adds a new
[`isMultiWindowEnabled`](https://github.com/flutter/flutter/pull/168697/files#diff-c8dbd5cd3103bc5be53c4ac5be8bdb9bf73e10cd5d8e4ac34e737fd1f8602d45R7-R11)
property to the framework.
4. The Material library can use this new property to determine whether
it should create a new window.
[Example](https://github.com/flutter/flutter/pull/168697/files#diff-2cbc1634ed6b61d61dfa090e7bfbbb7c60b74c8abc3a28df6f79eee691fd1b73).

## Limitations

### Tool and framework only

For now, these feature flags are available only to the Flutter tool and
Flutter framework. The flags are not automatically available to the
embedder or the engine.

For example, embedders need to configure their surfaces differently if
Impeller is enabled. This configuration must happen before the Dart
isolate is launched. As a result, the framework's feature flags is not a
viable solution for this scenario for now. For these kinds of scenarios,
we should continue to use platform-specific configuration like the
`AndroidManifest.xml` or `Info.plist` files.

This is a fixable limitation, we just need to invest in this plumbing :)

### Tree shaking

Feature flags are not designed to help tree shaking. For example, you
cannot conditionally import Dart code depending on the enabled feature
flags. Code that is feature flagged off will still be imported into
user's apps.

_⚠️ Landing this is blocked until: 1)
https://critique.corp.google.com/cl/781275353 lands and 2) google3 is
updated to add the new feature flag introduced in
flutter#171903

Currently, google3's `Google3Features` extends `FeatureFlags`. As a
result, google3 automatically gets the same feature flag values as in
Flutter.

This makes Flutter's feature flag values abstract, thereby requiring
that google3's `Google3Features` must explicitly set each feature flag's
value.

Discussion that motivated this change:
flutter#171797
Internal CL: https://critique.corp.google.com/cl/781275353
Part of: flutter#167668

## Pre-launch Checklist

- [x] I read the [Contributor Guide] and followed the process outlined
there for submitting PRs.
- [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 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].

<!-- Links -->
[Contributor Guide]:
https://github.com/flutter/flutter/blob/main/docs/contributing/Tree-hygiene.md#overview
[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

This relands flutter#168437. The google3
fixes were landed in: flutter#171547,
https://critique.corp.google.com/cl/781275353,
flutter#171933.

This PR is split into two commits:

1. d625379, code from
flutter#168437 without any changes
2. f35d29e, updates the PR to omit
obvious types.

Original PR description:

## Motivation

We'd like to let users opt-in to experimental features so that they can
give early feedback while we iterate on the feature. For example:

Example feature flags:

1. Android sensitive content:
flutter#158473. When enabled, Flutter
will tell Android when the view contains sensitive content like a
password.
3. Desktop multi-window. When enabled, Flutter will use child windows to
allow things like a context menu to "escape" outside of the current
window.

### Use case

Users will be able to turn on features by:

* **Option 1**: Run `flutter config --enable-my-feature`. This enables
the feature for all projects on the machine
* **Option 2**: Add `enable-my-feature: true` in their `pubspec.yaml`,
under the `flutter` section. This would enable the for a single project
on the machine.

Turning on a feature affects _both_ development-time (`flutter run`) and
deployment-time (`flutter build x`). For example, I can `flutter build
windows` to create an `.exe` with multi-window features enabled.

## How this works

This adds a new
[`runtimeId`](https://github.com/flutter/flutter/pull/168437/files#diff-0ded384225f19a4c34d43c7c11f7cb084ff3db947cfa82d8d52fc94c112bb2a7R243-R247)
property to the tool's `Feature` class. If a feature is on and has a
`runtimeId`, its `runtimeId` will be [stamped into the Dart application
as a Dart
define](https://github.com/flutter/flutter/pull/168437/files#diff-bd662448bdc2e6f50e47cd3b20b22b41a828561bce65cb4d54ea4f5011cc604eR293-R327).
The framework uses this Dart define to [determine which features are
enabled](https://github.com/flutter/flutter/pull/168437/files#diff-c8dbd5cd3103bc5be53c4ac5be8bdb9bf73e10cd5d8e4ac34e737fd1f8602d45).

### Multi-window example

flutter#168697 shows how this new
feature flag system can be used to add a multi-window feature flag:

1. It adds a new [multi-window
feature](https://github.com/flutter/flutter/pull/168697/files#diff-0ded384225f19a4c34d43c7c11f7cb084ff3db947cfa82d8d52fc94c112bb2a7R189-R198)
to the Flutter tool. This can be turned on using `flutter config
--enable-multi-window` or by putting `enable-multi-window: true` in an
app's .pubspec, under the `flutter` section.
2. It adds a new
[`isMultiWindowEnabled`](https://github.com/flutter/flutter/pull/168697/files#diff-c8dbd5cd3103bc5be53c4ac5be8bdb9bf73e10cd5d8e4ac34e737fd1f8602d45R7-R11)
property to the framework.
4. The Material library can use this new property to determine whether
it should create a new window.
[Example](https://github.com/flutter/flutter/pull/168697/files#diff-2cbc1634ed6b61d61dfa090e7bfbbb7c60b74c8abc3a28df6f79eee691fd1b73).

## Limitations

### Tool and framework only

For now, these feature flags are available only to the Flutter tool and
Flutter framework. The flags are not automatically available to the
embedder or the engine.

For example, embedders need to configure their surfaces differently if
Impeller is enabled. This configuration must happen before the Dart
isolate is launched. As a result, the framework's feature flags is not a
viable solution for this scenario for now. For these kinds of scenarios,
we should continue to use platform-specific configuration like the
`AndroidManifest.xml` or `Info.plist` files.

This is a fixable limitation, we just need to invest in this plumbing :)

### Tree shaking

Feature flags are not designed to help tree shaking. For example, you
cannot conditionally import Dart code depending on the enabled feature
flags. Code that is feature flagged off will still be imported into
user's apps.

…r#9602)

Roll Flutter from 43657f3baa17 to 35f197f1e5f5 (39 revisions)

flutter/flutter@43657f3...35f197f

2025-07-12 [email protected] Roll Fuchsia Linux SDK from 8aoEy1hp2a9HI1pt-... to xQlbHCUI33kDvkew8... (flutter/flutter#172060)
2025-07-12 [email protected] Add RSuperellipse support to Web (global cache) (flutter/flutter#171489)
2025-07-12 [email protected] Fix grammar: Change 'A' to 'An' before IOSSystemContextMenuItemData (flutter/flutter#172019)
2025-07-11 [email protected] Manual roll Dart to b21dca1b89ff (flutter/flutter#172038)
2025-07-11 [email protected] Roll Skia from 2ea2ba09ef85 to 92354f64e37f (1 revision) (flutter/flutter#172039)
2025-07-11 [email protected] Fix CheckedPopupMenuItem semantics to use menuItemCheckbox role with checked state (flutter/flutter#171749)
2025-07-11 [email protected] adds gemini.md to `engine` and `licenses_cpp` (flutter/flutter#172022)
2025-07-11 [email protected] [Web] Implement disabling interactive selection (flutter/flutter#171935)
2025-07-11 [email protected] [tool] Make google3 have to override feature flags (flutter/flutter#171933)
2025-07-11 [email protected] License cpp 710 (flutter/flutter#171989)
2025-07-11 [email protected] add content description to tooltip-only nodes for android (flutter/flutter#171541)
2025-07-11 [email protected] [Web a11y]Update table cell to use LabelRepresentation.sizedSpan  (flutter/flutter#172013)
2025-07-11 [email protected] [ Tool ] Enable `omit_obvious_*_types` and `specify_nonobvious_*_types` lints (flutter/flutter#172018)
2025-07-11 [email protected] Add SemanticsLabelBuilder for Accessible Label Concatenation (flutter/flutter#171683)
2025-07-11 [email protected] Run tests on either macOS 14 or 15 (flutter/flutter#171076)
2025-07-11 [email protected] Roll Skia from db1a5550c848 to 2ea2ba09ef85 (1 revision) (flutter/flutter#172017)
2025-07-11 [email protected] [Cupertino] Make some widgets no longer use RSuperellipse (flutter/flutter#171830)
2025-07-11 [email protected] Detach the resource context from the IO thread only if the shell's IO manager is no longer being used by any other spawned shells (flutter/flutter#171554)
2025-07-11 [email protected] Started querying the app state for the gpu disabled sync switch (flutter/flutter#171785)
2025-07-11 [email protected] License_cpp 7/02 (flutter/flutter#171558)
2025-07-11 [email protected] [web] Refactor clipboard. (flutter/flutter#171427)
2025-07-11 [email protected] Require 64-bit Windows (flutter/flutter#171925)
2025-07-11 [email protected] Run hot_reload_with_asset_web_test.dart on Mac/Windows (flutter/flutter#171280)
2025-07-11 [email protected] Roll Skia from da7e3eae7c2b to db1a5550c848 (2 revisions) (flutter/flutter#171999)
2025-07-11 [email protected] Roll Skia from 26571c3b1771 to da7e3eae7c2b (2 revisions) (flutter/flutter#171997)
2025-07-11 [email protected] Roll Skia from 34a40032ff0a to 26571c3b1771 (1 revision) (flutter/flutter#171995)
2025-07-11 [email protected] Roll Fuchsia Linux SDK from lO64ePNEGrGzs-MFC... to 8aoEy1hp2a9HI1pt-... (flutter/flutter#171993)
2025-07-10 [email protected] Remove redundant ThemeData(useMaterial3: true) from tests (flutter/flutter#171569)
2025-07-10 [email protected] [Android 16] Updated linux_android_emu to a 36 AVD in framework CI (flutter/flutter#169121)
2025-07-10 [email protected] [iOS] Add Live Text option to system context menu (flutter/flutter#170969)
2025-07-10 [email protected] Roll Skia from dc3da09ca905 to 34a40032ff0a (1 revision) (flutter/flutter#171982)
2025-07-10 [email protected] feat: Expose FocusNode of FocusTraversalGroup (flutter/flutter#171979)
2025-07-10 [email protected] `CupertinoDatePicker` and `CupertinoTimerPicker` new onChanged behavior (flutter/flutter#170793)
2025-07-10 [email protected] Manual roll Dart SDK from 8d69b07b9d9d to 07ea3aaaadf0 (32 revisions) (flutter/flutter#171969)
2025-07-10 [email protected] Style: Rename pageBuilder with builder in showCupertinoSheet (flutter/flutter#170625)
2025-07-10 [email protected] Roll Skia from bdb8bfcde7f3 to dc3da09ca905 (3 revisions) (flutter/flutter#171971)
2025-07-10 [email protected] Feat: Add foreground color for cupertino button (flutter/flutter#170898)
2025-07-10 [email protected] Roll Skia from 0fef076beec3 to bdb8bfcde7f3 (34 revisions) (flutter/flutter#171964)
2025-07-10 [email protected] Run stateless_stateful_hot_reload_web_test.dart on Mac/Windows (flutter/flutter#171283)

If this roll has caused a breakage, revert this CL and stop the roller
using the controls here:
https://autoroll.skia.org/r/flutter-packages
Please CC [email protected],[email protected] on the revert to ensure that a human
is aware of the problem.

...

…/flutter#171933)

…/flutter#171933)

…/flutter#171933)

…/flutter#171933)

…/flutter#171933)

_⚠️ Landing this is blocked until: 1)
https://critique.corp.google.com/cl/781275353 lands and 2) google3 is
updated to add the new feature flag introduced in
flutter#171903

Currently, google3's `Google3Features` extends `FeatureFlags`. As a
result, google3 automatically gets the same feature flag values as in
Flutter.

This makes Flutter's feature flag values abstract, thereby requiring
that google3's `Google3Features` must explicitly set each feature flag's
value.

Discussion that motivated this change:
flutter#171797
Internal CL: https://critique.corp.google.com/cl/781275353
Part of: flutter#167668

## Pre-launch Checklist

- [x] I read the [Contributor Guide] and followed the process outlined
there for submitting PRs.
- [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 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].

<!-- Links -->
[Contributor Guide]:
https://github.com/flutter/flutter/blob/main/docs/contributing/Tree-hygiene.md#overview
[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

This relands flutter#168437. The google3
fixes were landed in: flutter#171547,
https://critique.corp.google.com/cl/781275353,
flutter#171933.

This PR is split into two commits:

1. d625379, code from
flutter#168437 without any changes
2. f35d29e, updates the PR to omit
obvious types.

Original PR description:

## Motivation

We'd like to let users opt-in to experimental features so that they can
give early feedback while we iterate on the feature. For example:

Example feature flags:

1. Android sensitive content:
flutter#158473. When enabled, Flutter
will tell Android when the view contains sensitive content like a
password.
3. Desktop multi-window. When enabled, Flutter will use child windows to
allow things like a context menu to "escape" outside of the current
window.

### Use case

Users will be able to turn on features by:

* **Option 1**: Run `flutter config --enable-my-feature`. This enables
the feature for all projects on the machine
* **Option 2**: Add `enable-my-feature: true` in their `pubspec.yaml`,
under the `flutter` section. This would enable the for a single project
on the machine.

Turning on a feature affects _both_ development-time (`flutter run`) and
deployment-time (`flutter build x`). For example, I can `flutter build
windows` to create an `.exe` with multi-window features enabled.

## How this works

This adds a new
[`runtimeId`](https://github.com/flutter/flutter/pull/168437/files#diff-0ded384225f19a4c34d43c7c11f7cb084ff3db947cfa82d8d52fc94c112bb2a7R243-R247)
property to the tool's `Feature` class. If a feature is on and has a
`runtimeId`, its `runtimeId` will be [stamped into the Dart application
as a Dart
define](https://github.com/flutter/flutter/pull/168437/files#diff-bd662448bdc2e6f50e47cd3b20b22b41a828561bce65cb4d54ea4f5011cc604eR293-R327).
The framework uses this Dart define to [determine which features are
enabled](https://github.com/flutter/flutter/pull/168437/files#diff-c8dbd5cd3103bc5be53c4ac5be8bdb9bf73e10cd5d8e4ac34e737fd1f8602d45).

### Multi-window example

flutter#168697 shows how this new
feature flag system can be used to add a multi-window feature flag:

1. It adds a new [multi-window
feature](https://github.com/flutter/flutter/pull/168697/files#diff-0ded384225f19a4c34d43c7c11f7cb084ff3db947cfa82d8d52fc94c112bb2a7R189-R198)
to the Flutter tool. This can be turned on using `flutter config
--enable-multi-window` or by putting `enable-multi-window: true` in an
app's .pubspec, under the `flutter` section.
2. It adds a new
[`isMultiWindowEnabled`](https://github.com/flutter/flutter/pull/168697/files#diff-c8dbd5cd3103bc5be53c4ac5be8bdb9bf73e10cd5d8e4ac34e737fd1f8602d45R7-R11)
property to the framework.
4. The Material library can use this new property to determine whether
it should create a new window.
[Example](https://github.com/flutter/flutter/pull/168697/files#diff-2cbc1634ed6b61d61dfa090e7bfbbb7c60b74c8abc3a28df6f79eee691fd1b73).

## Limitations

### Tool and framework only

For now, these feature flags are available only to the Flutter tool and
Flutter framework. The flags are not automatically available to the
embedder or the engine.

For example, embedders need to configure their surfaces differently if
Impeller is enabled. This configuration must happen before the Dart
isolate is launched. As a result, the framework's feature flags is not a
viable solution for this scenario for now. For these kinds of scenarios,
we should continue to use platform-specific configuration like the
`AndroidManifest.xml` or `Info.plist` files.

This is a fixable limitation, we just need to invest in this plumbing :)

### Tree shaking

Feature flags are not designed to help tree shaking. For example, you
cannot conditionally import Dart code depending on the enabled feature
flags. Code that is feature flagged off will still be imported into
user's apps.

_⚠️ Landing this is blocked until: 1)
https://critique.corp.google.com/cl/781275353 lands and 2) google3 is
updated to add the new feature flag introduced in
flutter#171903

Currently, google3's `Google3Features` extends `FeatureFlags`. As a
result, google3 automatically gets the same feature flag values as in
Flutter.

This makes Flutter's feature flag values abstract, thereby requiring
that google3's `Google3Features` must explicitly set each feature flag's
value.

Discussion that motivated this change:
flutter#171797
Internal CL: https://critique.corp.google.com/cl/781275353
Part of: flutter#167668

## Pre-launch Checklist

- [x] I read the [Contributor Guide] and followed the process outlined
there for submitting PRs.
- [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 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].

<!-- Links -->
[Contributor Guide]:
https://github.com/flutter/flutter/blob/main/docs/contributing/Tree-hygiene.md#overview
[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

This relands flutter#168437. The google3
fixes were landed in: flutter#171547,
https://critique.corp.google.com/cl/781275353,
flutter#171933.

This PR is split into two commits:

1. d625379, code from
flutter#168437 without any changes
2. f35d29e, updates the PR to omit
obvious types.

Original PR description:

## Motivation

We'd like to let users opt-in to experimental features so that they can
give early feedback while we iterate on the feature. For example:

Example feature flags:

1. Android sensitive content:
flutter#158473. When enabled, Flutter
will tell Android when the view contains sensitive content like a
password.
3. Desktop multi-window. When enabled, Flutter will use child windows to
allow things like a context menu to "escape" outside of the current
window.

### Use case

Users will be able to turn on features by:

* **Option 1**: Run `flutter config --enable-my-feature`. This enables
the feature for all projects on the machine
* **Option 2**: Add `enable-my-feature: true` in their `pubspec.yaml`,
under the `flutter` section. This would enable the for a single project
on the machine.

Turning on a feature affects _both_ development-time (`flutter run`) and
deployment-time (`flutter build x`). For example, I can `flutter build
windows` to create an `.exe` with multi-window features enabled.

## How this works

This adds a new
[`runtimeId`](https://github.com/flutter/flutter/pull/168437/files#diff-0ded384225f19a4c34d43c7c11f7cb084ff3db947cfa82d8d52fc94c112bb2a7R243-R247)
property to the tool's `Feature` class. If a feature is on and has a
`runtimeId`, its `runtimeId` will be [stamped into the Dart application
as a Dart
define](https://github.com/flutter/flutter/pull/168437/files#diff-bd662448bdc2e6f50e47cd3b20b22b41a828561bce65cb4d54ea4f5011cc604eR293-R327).
The framework uses this Dart define to [determine which features are
enabled](https://github.com/flutter/flutter/pull/168437/files#diff-c8dbd5cd3103bc5be53c4ac5be8bdb9bf73e10cd5d8e4ac34e737fd1f8602d45).

### Multi-window example

flutter#168697 shows how this new
feature flag system can be used to add a multi-window feature flag:

1. It adds a new [multi-window
feature](https://github.com/flutter/flutter/pull/168697/files#diff-0ded384225f19a4c34d43c7c11f7cb084ff3db947cfa82d8d52fc94c112bb2a7R189-R198)
to the Flutter tool. This can be turned on using `flutter config
--enable-multi-window` or by putting `enable-multi-window: true` in an
app's .pubspec, under the `flutter` section.
2. It adds a new
[`isMultiWindowEnabled`](https://github.com/flutter/flutter/pull/168697/files#diff-c8dbd5cd3103bc5be53c4ac5be8bdb9bf73e10cd5d8e4ac34e737fd1f8602d45R7-R11)
property to the framework.
4. The Material library can use this new property to determine whether
it should create a new window.
[Example](https://github.com/flutter/flutter/pull/168697/files#diff-2cbc1634ed6b61d61dfa090e7bfbbb7c60b74c8abc3a28df6f79eee691fd1b73).

## Limitations

### Tool and framework only

For now, these feature flags are available only to the Flutter tool and
Flutter framework. The flags are not automatically available to the
embedder or the engine.

For example, embedders need to configure their surfaces differently if
Impeller is enabled. This configuration must happen before the Dart
isolate is launched. As a result, the framework's feature flags is not a
viable solution for this scenario for now. For these kinds of scenarios,
we should continue to use platform-specific configuration like the
`AndroidManifest.xml` or `Info.plist` files.

This is a fixable limitation, we just need to invest in this plumbing :)

### Tree shaking

Feature flags are not designed to help tree shaking. For example, you
cannot conditionally import Dart code depending on the enabled feature
flags. Code that is feature flagged off will still be imported into
user's apps.

_⚠️ Landing this is blocked until: 1)
https://critique.corp.google.com/cl/781275353 lands and 2) google3 is
updated to add the new feature flag introduced in
flutter#171903

Currently, google3's `Google3Features` extends `FeatureFlags`. As a
result, google3 automatically gets the same feature flag values as in
Flutter.

This makes Flutter's feature flag values abstract, thereby requiring
that google3's `Google3Features` must explicitly set each feature flag's
value.

Discussion that motivated this change:
flutter#171797
Internal CL: https://critique.corp.google.com/cl/781275353
Part of: flutter#167668

## Pre-launch Checklist

- [x] I read the [Contributor Guide] and followed the process outlined
there for submitting PRs.
- [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 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].

<!-- Links -->
[Contributor Guide]:
https://github.com/flutter/flutter/blob/main/docs/contributing/Tree-hygiene.md#overview
[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

This relands flutter#168437. The google3
fixes were landed in: flutter#171547,
https://critique.corp.google.com/cl/781275353,
flutter#171933.

This PR is split into two commits:

1. d625379, code from
flutter#168437 without any changes
2. f35d29e, updates the PR to omit
obvious types.

Original PR description:

## Motivation

We'd like to let users opt-in to experimental features so that they can
give early feedback while we iterate on the feature. For example:

Example feature flags:

1. Android sensitive content:
flutter#158473. When enabled, Flutter
will tell Android when the view contains sensitive content like a
password.
3. Desktop multi-window. When enabled, Flutter will use child windows to
allow things like a context menu to "escape" outside of the current
window.

### Use case

Users will be able to turn on features by:

* **Option 1**: Run `flutter config --enable-my-feature`. This enables
the feature for all projects on the machine
* **Option 2**: Add `enable-my-feature: true` in their `pubspec.yaml`,
under the `flutter` section. This would enable the for a single project
on the machine.

Turning on a feature affects _both_ development-time (`flutter run`) and
deployment-time (`flutter build x`). For example, I can `flutter build
windows` to create an `.exe` with multi-window features enabled.

## How this works

This adds a new
[`runtimeId`](https://github.com/flutter/flutter/pull/168437/files#diff-0ded384225f19a4c34d43c7c11f7cb084ff3db947cfa82d8d52fc94c112bb2a7R243-R247)
property to the tool's `Feature` class. If a feature is on and has a
`runtimeId`, its `runtimeId` will be [stamped into the Dart application
as a Dart
define](https://github.com/flutter/flutter/pull/168437/files#diff-bd662448bdc2e6f50e47cd3b20b22b41a828561bce65cb4d54ea4f5011cc604eR293-R327).
The framework uses this Dart define to [determine which features are
enabled](https://github.com/flutter/flutter/pull/168437/files#diff-c8dbd5cd3103bc5be53c4ac5be8bdb9bf73e10cd5d8e4ac34e737fd1f8602d45).

### Multi-window example

flutter#168697 shows how this new
feature flag system can be used to add a multi-window feature flag:

1. It adds a new [multi-window
feature](https://github.com/flutter/flutter/pull/168697/files#diff-0ded384225f19a4c34d43c7c11f7cb084ff3db947cfa82d8d52fc94c112bb2a7R189-R198)
to the Flutter tool. This can be turned on using `flutter config
--enable-multi-window` or by putting `enable-multi-window: true` in an
app's .pubspec, under the `flutter` section.
2. It adds a new
[`isMultiWindowEnabled`](https://github.com/flutter/flutter/pull/168697/files#diff-c8dbd5cd3103bc5be53c4ac5be8bdb9bf73e10cd5d8e4ac34e737fd1f8602d45R7-R11)
property to the framework.
4. The Material library can use this new property to determine whether
it should create a new window.
[Example](https://github.com/flutter/flutter/pull/168697/files#diff-2cbc1634ed6b61d61dfa090e7bfbbb7c60b74c8abc3a28df6f79eee691fd1b73).

## Limitations

### Tool and framework only

For now, these feature flags are available only to the Flutter tool and
Flutter framework. The flags are not automatically available to the
embedder or the engine.

For example, embedders need to configure their surfaces differently if
Impeller is enabled. This configuration must happen before the Dart
isolate is launched. As a result, the framework's feature flags is not a
viable solution for this scenario for now. For these kinds of scenarios,
we should continue to use platform-specific configuration like the
`AndroidManifest.xml` or `Info.plist` files.

This is a fixable limitation, we just need to invest in this plumbing :)

### Tree shaking

Feature flags are not designed to help tree shaking. For example, you
cannot conditionally import Dart code depending on the enabled feature
flags. Code that is feature flagged off will still be imported into
user's apps.