Guard removePointer with addTearDown to avoid cascading test crash.

Re-land "[Material] Support for hovered, focused, and pressed border color on `OutlineButton`s" (#35278)

* outline border implements material state property

Revert "[Material] Support for hovered, focused, and pressed border color on `OutlineButton`s (#34872)" (#35276)

This reverts commit 3f941599.

* outline border implements material state property

* Support for stateful text colors in buttons

* Add color and a11y tests for buttons

This implements focus and hover handling for Material buttons. It inserts Focus widgets into the tree in order to allow buttons to be focusable via keyboard traversal (a.k.a. TAB traversal), and Listener widgets into the InkWell to allow the detection of hover states for widgets.

Addresses #11344, #1608, and #13264.

* Re-enable const

* Composite physical layers even if elevation is 0

This reverts commit 803b15e0.

Reland composite physical layers and update tests

This reverts commit 58fb1832.

* Always composite PhysicalModels
* Update tests to check layer tree instead of canvas for Physical shadows

* 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

These changes are **backwards incompatible**. Tests that verify OutlineButton visuals, for example golden image tests, will need to be updated.

Previously, a disabled floating action button always had zero
elevation, which looks dumb.

This also fixes the issue whereby highlightElevation was not honoured
on floating action buttons.

This also fixes an issue I found during testing whereby setState was
being called during build when onHighlightChanged fired due to
onPressed becoming null while a gesture is ongoing (which triggers an
onTapCancel synchronously during build).

This reverts commit 80f80ab0.

For G3 Roll:

* Revert "MaterialButton must honor its minWidth and height parameters (#22919)"

This reverts commit a0233233.

* Revert "Update uses of ButtonTheme.bar: pass along the current Theme's colorScheme (#22827)"

This reverts commit 655bf6a2.

* Revert "ButtonTheme.of().colorScheme defers to Theme (#22880)"

This reverts commit a590940e.

* Revert "Bring TextTheme into alignment with the current Material spec (#22330)"

This reverts commit 8bfb4b3e.

* Revert "Added ColorScheme, updated ThemeData, ButtonTheme, material buttons (#22013)"

This reverts commit eea3465a.

* Manual adjustments to fix reversion issues.

Introduce an overall material "color scheme" and to make it possible to redefine how a component's visual properties bind to the color scheme and to the existing material Theme.

* enable lint unnecessary_new

* fix tests

* fix tests

* fix tests

This reverts commit 8de0e15e and
updates the goldens versoin.

This requires https://github.com/flutter/flutter/pull/20751 to
land first.

Fixes the pattern for some TODOs to match our style guide.

(Also, a couple of minor code order fixes.)

This fixes https://github.com/flutter/flutter/issues/18057

* Create test case for disabled state of outline button

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.