* add missing trailing commas

* add more missing trailing commas

* add more and more missing trailing commas

* Add DefaultTextStyle parent widget to Tooltip Overlay

* Add test against fallback DefaultTextStyle

Guard removePointer with addTearDown to avoid cascading test crash.

* Add margin parameter to tooltips

* Improve tooltip tests to find the tooltip's `Container` instead of arbitrary number of parent calls

* Improve showDuration and waitDuration explanation and tests

* Add condition to test to ensure that tooltip does not show before long press duration is over

* Implement TooltipThemeData and TooltipTheme

* Add text style property 

* Updated tooltip default colors for light and dark theme to match Material specification

Revert "[Material] Implement TooltipTheme and Tooltip.textStyle, fix Tooltip debugLabel, update Tooltip defaults (#36030)" (#36851)

This reverts commit 62158a1b.

[Material] Implement TooltipTheme and Tooltip.textStyle, fix Tooltip debugLabel, update Tooltip defaults (#36030)

* Implement TooltipThemeData and TooltipTheme

* Add tooltip text style property

* Update default tooltip text style and decoration to match Material specification

* Fix debugLabel incorrectly labeling "white" as "black", and vice versa by default

This is a re-land of #31561, after fixing performance regressions.

Added change listening to the MouseTracker so that the Listener and tooltip can react to whether or not a mouse is connected at all. Added a change check to make sure Listener only repaints when something changed.

Fixes #22817

This reverts commit eca93640 because of four
performance regressions. Will fix and re-land.

Adds support for mouse pointer hovering to trigger tooltips, as well as custom timeouts for the tooltip durations, and a custom decoration. It also makes the tooltip be fully opaque when shown, and fade in over 150ms, and fade out over 75ms, and draw a 4.0 corner radius, all to conform with the material spec. Prior to this change, it was using a corner radius of 2.0 when shown, and faded in and out over 200ms.

Fixes #22817

* add trailing commas on list/map/parameters

* add trailing commas on Invocation with nb of arg>1

* add commas for widget containing widgets

* add trailing commas if instantiation contains trailing comma

* revert bad change

## Description

Also update the existing dart files with missing licenses.

Without the fix, we'll emit the following error message
```
License headers cannot be found at the beginning of the following files.

/usr/local/google/home/liyuqian/flutter/flutter/packages/flutter/lib/src/animation/tween_sequence.dart
/usr/local/google/home/liyuqian/flutter/flutter/packages/flutter/test/material/raw_material_button_test.dart
/usr/local/google/home/liyuqian/flutter/flutter/packages/flutter/test/widgets/async_lifecycle_test.dart
/usr/local/google/home/liyuqian/flutter/flutter/packages/flutter/test/widgets/sliver_constraints_test.dart
/usr/local/google/home/liyuqian/flutter/flutter/packages/flutter/test/widgets/app_test.dart
/usr/local/google/home/liyuqian/flutter/flutter/packages/flutter/test/widgets/test_border.dart
/usr/local/google/home/liyuqian/flutter/flutter/packages/flutter/test/widgets/physical_model_test.dart
/usr/local/google/home/liyuqian/flutter/flutter/packages/flutter/test/widgets/inherited_model.dart
/usr/local/google/home/liyuqian/flutter/flutter/packages/flutter_tools/lib/src/base/user_messages.dart
/usr/local/google/home/liyuqian/flutter/flutter/packages/flutter_tools/test/src/pubspec_schema.dart
/usr/local/google/home/liyuqian/flutter/flutter/packages/flutter_tools/test/ios/simulators_test.dart
━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
```

## Related Issues

Fixes https://github.com/flutter/flutter/issues/28368

## Checklist

Before you create this PR confirm that it meets all requirements listed below by checking the relevant checkboxes (`[x]`). This will ensure a smooth and quick review process.

- [x] I read the [Contributor Guide] and followed the process outlined there for submitting PRs.
- [x] My PR includes tests for *all* changed/updated/fixed behaviors (See [Test Coverage]).
- [x] All existing and new tests are passing.
- [x] I updated/added relevant documentation (doc comments with `///`).
- [x] The analyzer (`flutter analyze --flutter-repo`) does not report any problems on my PR.
- [x] I read and followed the [Flutter Style Guide], including [Features we expect every widget to implement].
- [x] I signed the [CLA].
- [x] I am willing to follow-up on review comments in a timely manner.

## Breaking Change

Does your PR require Flutter developers to manually update their apps to accommodate your change?

- [ ] Yes, this is a breaking change (Please read [Handling breaking changes]).
- [x] No, this is *not* a breaking change.

<!-- Links -->
[issue database]: https://github.com/flutter/flutter/issues
[Contributor Guide]: https://github.com/flutter/flutter/wiki/Tree-hygiene#overview
[Test Coverage]: https://github.com/flutter/flutter/wiki/Test-coverage-for-package%3Aflutter
[Flutter Style Guide]: https://github.com/flutter/flutter/wiki/Style-guide-for-Flutter-repo
[Features we expect every widget to implement]: https://github.com/flutter/flutter/wiki/Style-guide-for-Flutter-repo#features-we-expect-every-widget-to-implement
[CLA]: https://cla.developers.google.com/
[Handling breaking changes]: https://github.com/flutter/flutter/wiki/Tree-hygiene#handling-breaking-changes

* Refactor of cupertino/material/widgets app

* update docs 

* Update tests for const

This reverts commit 61cf946b.

* Make CupertinoApp and MaterialApp both use WidgetsApp for Navigator

* Make CupertinoApp and MaterialApp const constructors

* Make WidgetsApp routes aware

* Update tests

* enable lint unnecessary_new

* fix tests

* fix tests

* fix tests

It was causing problems rolling Flutter into Fuchsia

* re-enable lint unnecessary_const

* remove trailling whitespaces

* remove unnecessary const (after merge)

This reverts commit cc1cf13e.

Revert longPress/Tap and Gallery changes

* Set text direction in semantics along with Directionality

* update tests for the extra SemanticsNode

Semantics object support for edge triggered semantics 

This is not a grand refactor yet, it's just cleaning up what we have
already, so that people who keep using this API (e.g. dialogs) have
something coherent to deal with.

The major changes are that Navigator and NavigatorState have the same
API now, that most of the examples use `<void>` instead of `<Null>`,
that the navigator observer can see replaces, and that the `settings`
is moved from ModalRoute to Route. I also cleaned up some of the API
documentation.

* Oct 12 10:12am

* implicit_semantics_test.dart passes

* refactoring

* works in nice

* minor rename

* more doc comments

* to be explicit check better

* fix test

* ++

* ++

* semantics_9_test (BlockSemantics) and implicit_semantics_test are passing

* doc updates

* tiny refactor

* fix static errors in tests

* fix gesture detector

* ++

* ++

* geometry

* ++

* remove noGeometry

* revert test

* +

* all tests but scrolling/clipping pass

* clipping works

* scrolling halfway

* sliver tests pass

* ALL TESTS PASS

* SemanticsNode changed

* docs and tiny fixes

* card test

* more doc comments

* remove missed print

* more tests

* make test pass on Linux

* remove changes to intellij proj file

* review comments

Fixes #12480

* Provide haptic/acoustic feedback for tap & long-press on Android

* review comments

* fixed example code

* review comments

* comment fix

Previously we used logical pixels. This made the accessibility metrics
tiny on modern devices, since the OS works in physical units.

Also add a bit more debugging info and some docs.

backgroundColor -> color
backgroundImage -> image
BackgroundImage -> DecorationImage

* Manually fix every use of Point.x and Point.y

Some of these were moved to dx/dy, but not all.

* Manually convert uses of the old gradient API

* Remove old reference to Point.

* Mechanical changes

I applied the following at the root of the Flutter repository:

git ls-files -z | xargs -0 sed -i 's/\bPoint[.]origin\b/Offset.zero/g'
git ls-files -z | xargs -0 sed -i 's/\bPoint[.]lerp\b/Offset.lerp/g'
git ls-files -z | xargs -0 sed -i 's/\bnew Point\b/new Offset/g'
git ls-files -z | xargs -0 sed -i 's/\bconst Point\b/const Offset/g'
git ls-files -z | xargs -0 sed -i 's/\bstatic Point /static Offset /g'
git ls-files -z | xargs -0 sed -i 's/\bfinal Point /final Offset /g'
git ls-files -z | xargs -0 sed -i 's/^\( *\)Point /\1Offset /g'
git ls-files -z | xargs -0 sed -i 's/ui[.]Point\b/ui.Offset/g'
git ls-files -z | xargs -0 sed -i 's/(Point\b/(Offset/g'
git ls-files -z | xargs -0 sed -i 's/\([[{,]\) Point\b/\1 Offset/g'
git ls-files -z | xargs -0 sed -i 's/@required Point\b/@required Offset/g'
git ls-files -z | xargs -0 sed -i 's/<Point>/<Offset>/g'
git ls-files -z | xargs -0 sed -i 's/[.]toOffset()//g'
git ls-files -z | xargs -0 sed -i 's/[.]toPoint()//g'
git ls-files -z | xargs -0 sed -i 's/\bshow Point, /show /g'
git ls-files -z | xargs -0 sed -i 's/\bshow Point;/show Offset;/g'

* Mechanical changes - dartdocs

I applied the following at the root of the Flutter repository:

git ls-files -z | xargs -0 sed -i 's/\ba \[Point\]/an [Offset]/g'
git ls-files -z | xargs -0 sed -i 's/\[Point\]/[Offset]/g'

* Further improvements and a test

* Fix minor errors from rebasing...

* Roll engine

We were trying to update the tooltip overlay entry, but that cannot work
because the overlay entry might have already built. Instead, we keep the
old value.

Fixes #7151