Reland "Prevent material switch from recreating its render object when it becomes disabled (#61398)", reverted in #64062 (#64354)

Revert "Prevent material switch from recreating its render object when it becomes disabled (#61398)" (#64062)

* add language version 2.8 in packages/flutter

* enable non-nullable analyzer flag

* Adds default cursor and/or mouseCursor property to a number of widgets.
* Adds `MaterialStateMouseCurrsor`.

This re-lands #49235 with the addition of includeSemantics flag on the Focus widget so that the FocusTraversalGroup can create a Focus widget without affecting the semantics tree.

The FocusTraversalGroup uses the Focus widget to create a grouping of descendants for traversal, but doesn't actually participate in focus (canRequestFocus is always false), so we don't want it to add a Semantics widget in that case, since that can cause semantics changes. The canRequestFocus attribute can also be used when a widget is disabled, so we do sometimes want to include Semantics even if that is false, but not in the case where it is always false, as for FocusTraversalGroup.

- Added a test to make sure that FocusTraversalGroup doesn't add any semantics information.

This reverts commit 8ef5e2f0 because it breaks some semantics tests.

This change adds a way to provide explicit focus order for a part of the widget tree.

It adds FocusTraversalPolicyGroup, which in many ways is similar to DefaultFocusTraversal, except that it groups a widget subtree together so that those nodes are traversed as a group. DefaultFocusTraversal doesn't work as one would expect: If there is more than one DefaultFocusTraversal inside of a focus scope, the policy can change depending on which node was asked to move "next", which can cause unexpected behavior. The new grouping mechanism doesn't have that problem. I deprecate DefaultFocusTraversal in this PR.

It also adds OrderedFocusTraversalPolicy, which is a policy that can be supplied to FocusTraversalPolicyGroup to set the policy for a sub-tree. It looks for FocusTraversalOrder inherited widgets, which use a FocusOrder to do the sorting. FocusOrder has two subclasses: NumericalFocusOrder (which sorts based on a double), and LexicalFocusOrder, which sorts based on a String.

As part of doing this, I refactored the way FocusTraversalPolicy is implemented so that it has more default implementation methods, and exposes a new protected member: sortDescendants, which makes it easier for developers to make their own policy subclasses: they only need to implement sortDescendants to get a new ordering behavior, but can also still override any of the default implementation behaviors if they need different behavior.

I was able to do this without breaking the API (AFAICT).

This adds a visualDensity attribute to checkbox, radio, icon button, and chip.

* Update project.pbxproj files to say Flutter rather than Chromium

Also, the templates now have an empty organization so that we don't cause people to give their apps a Flutter copyright.

* Update the copyright notice checker to require a standard notice on all files

* Update copyrights on Dart files. (This was a mechanical commit.)

* Fix weird license headers on Dart files that deviate from our conventions; relicense Shrine.

Some were already marked "The Flutter Authors", not clear why. Their
dates have been normalized. Some were missing the blank line after the
license. Some were randomly different in trivial ways for no apparent
reason (e.g. missing the trailing period).

* Clean up the copyrights in non-Dart files. (Manual edits.)

Also, make sure templates don't have copyrights.

* Fix some more ORGANIZATIONNAMEs

This adds a FocusableActionDetector, a widget which combines the functionality of Actions, Shortcuts, MouseRegion and a Focus widget to create a detector that defines actions and key bindings, and will notify that the focus or hover highlights should be shown or not. This widget can be used to give a control the required detection modes for focus and hover handling on desktop and web platforms.

I replaced a bunch of similar code in many of our widgets with this widget, and found that pretty much any control that wants to be focusable wants all of these features as well: focus highlights, hover highlights, and actions to activate it.

Also eliminated an extra _hasFocus variable in FocusState that wasn't being used.

This re-lands the change that adds focus nodes, hover, and shortcuts to switches, checkboxes, and radio buttons. (#43213), with fixes for the web tests that weren't enabled in the master that it was synced to when I first landed it.

Revert "Re-Land: Add focus nodes, hover, and shortcuts to switches, checkboxes, and radio buttons. (#43384)" (#43647)

This reverts commit 8017f63b, since it breaks web tests.

This re-lands the change that adds focus nodes, hover, and shortcuts to switches, checkboxes, and radio buttons. (#43213)

No changes from original, except for finding the right RenderBox in dev/integration_tests/android_semantics_testing/test_driver/main_test.dart.

Revert "Add focus nodes, hover, and shortcuts to switches, checkboxes, and radio buttons. (#43213)" (#43367)

This reverts commit 90006720.

In order to enable keyboard navigation to more controls, I've added focus nodes to switches, checkboxes, and radio buttons. In addition, this change enables mouse hover over these controls.

- Added tests for focus, hover, and shortcut activation for Checkbox, Radio, and Switch.

* Add checkColor to CheckboxListTile

* Create second paint for drawing check and dash

* Add activeColor test for Checkbox
Co-Authored-By: Shi-Hao Hong <shihaohong@google.com>

* 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

The new parameter defines the color of the checkbox's check mark. Default is (still) white.

* 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.

This reverts commit 989f5741.

Revert longPress/Tap and Gallery changes