* Update parameters to the `styleFrom` button methods.

* Updated the Flutter fix data to point to this PR.

* Updated handling of background color to better maintain backwards compatibility with previous API.

* Added an example for IndexedStack

* Added tests for the IndexedStack example

* Fixed type issue for onSubmitted callback functions

* Fixed documentation and moved files to their appropriate places

* Fixed documentation and moved files to their appropriate places

* Moved test files to their appropriate places

* Moved test files to their appropriate places

* Fixed file path in documentation

* Remove trailing space

* Formatting changes

* Remove extra line

* Further formatting changes

* Further formatting changes

* fix comma and inline
Co-authored-by: Greg Spencer <gspencergoog@users.noreply.github.com>

* Formatting

* indentation and formatting

* Formatting

* Formatting

* Formatting

* Removed duplicate chevron

* better wording on documentation
Co-authored-by: Tong Mu <dkwingsmt@users.noreply.github.com>

* Added testing for state preservation
Co-authored-by: Greg Spencer <gspencergoog@users.noreply.github.com>
Co-authored-by: Tong Mu <dkwingsmt@users.noreply.github.com>

* Added standard IconButton for M3 with new ButtonStyle field

* Added IconButton examples for standard, filled, filled_tonal, and outlined types
Co-authored-by: Qun Cheng <quncheng@google.com>

This reverts commit 180566f2.

* more const immutable classes

* more const constructors in dev/ and examples/

When I was doing the MenuBar implementation, I made some changes to the PlatformMenuBar to allow it to understand shortcuts a little more, and to deprecate the body parameter rename it to child to match most other widgets.

These are those changes, separated out because they are separable, and I'm trying to make the MenuBar PR smaller.

* `Switch`: Add an interactive examples

* Update docs

* Update doc

* Support global selection

* addressing comments

* add new test

* Addressing review comments

* update

* addressing comments

* addressing comments

* Addressing comments

* fix build

* Add support for M3 AppBar 'Medium' and 'Large' types.

* Updates from review feedback.

* Updated from review feedback.

* Replace references to LinearProgressIndicator in CircularProgressIndicator example

* Add test

* fix copyright header

* `CupertinoTabScaffold`/`CupertinoTabController`: Add interactive examples

* fix class name in the test

* Kick tests

`DropdownButton`: Update `selectedItemBuilder` example to show case item alignment and update DropdownButton examples (#102748)

Update

* `CupertinoFormRow`: Add an interactive example

* fix typo

* Update docs

* `CupertinoSearchTextField`: Add interactive examples

* Update docs