Repository: flutter
Issue: ☂️ Material Theme System Updates
Labels: framework,f: material design,P2,c: tech-debt,team-design,triaged-design

This issue mirrors the design of https://flutter.dev/go/material-theme-system-updates

## Rename the TextTheme TextStyles
- [x] #48547
- [x] https://github.com/flutter/flutter/issues/98746

## Deprecate/remove the accent properties
- [x] https://github.com/flutter/flutter/issues/56918

## Compute `brightness`, `primaryColorBrightness`, `accentColorBrightness`
- [x] Deprecate `accentColorBrightness` #81336
- [x] Change `ThemeData.brightness` to be a simple getter that returns `colorScheme.brightness` #56956
- [x] Update `SearchDelegate` #55209
- [x] Update `GridTileBar` #78574
- [x] Deprecate `primaryColorBrightness` #93396

## Deprecate/move/remove the 21 grab-bag properties
(x) indicates number of references, excluding`theme_data.dart` and tests. This can be used a proxy for disruptiveness/ease of deprecation.

- [ ] Deprecate `ThemeData.canvasColor` #116350
- [ ] Deprecate `ThemeData.scaffoldBackgroundColor` #116341
- [ ] Deprecate `ThemeData.cardColor` #116349
- [ ] Deprecate `ThemeData.dividerColor` #116347
- [ ] Deprecate `ThemeData.secondaryHeaderColor` #116342
- [ ] Deprecate `ThemeData.hintColor` #116346
- [ ] Deprecate `ThemeData.splashColor` (5) ⇒ `inkColor` or `inkFeatureColor`
- [ ] Deprecate `ThemeData.unselectedWidgetColor` (11) ⇒ see `toggleableActiveColor` deprecation
- [x] Deprecate `ThemeData.bottomAppBarColor` ⇒ #111080
- [x] Deprecate `ThemeData.selectedRowColor` #109070
- [x] Deprecate `ThemeData.buttonColor` #82196
- [x] Deprecate `ThemeData.textSelectionColor` #66482
- [x] Deprecate `ThemeData.cursorColor` #66482
- [x] Deprecate `ThemeData.textSelectionHandleColor` #66482
- [x] Deprecate `ThemeData.backgroundColor` #110162
- [x] Deprecate `ThemeData.dialogBackgroundColor` #155072
- [x] Deprecate `ThemeData.indicatorColor` #160024
- [x] Deprecate `ThemeData.errorColor` #110162
- [x] Deprecate `ThemeData.toggleableActiveColor` #97972

### Additional grab-bag properties
These grab-bag properties not in the original linked proposal, but can also be deprecated:

- [ ] Deprecate `ThemeData.shadowColor` #116343
- [ ] Deprecate `ThemeData.splashFactory` (4) ⇒ `inkFactory` or `inkFeatureFactory`
- [ ] Deprecate `primaryColor` #110848
- [ ] Deprecate `primaryColorDark` #116362
- [ ] Deprecate `primaryColorLight` #116362
- [x] Deprecate `ThemeData.fixTextFieldOutlineLabel` #87281

These factory constructor parameters can also be deprecated:
- [ ] Deprecate `primarySwatch` from `ThemeData` factory constructor (8) ⇒ `colorScheme` or `colorSchemeSeedColor` (related https://github.com/flutter/flutter/issues/120064)

### Property colors not subject to removal
- State colors like `ThemeData.disabledColor` (26), `ThemeData.focusColor` (19), and `ThemeData.hoverColor` (19) have high usage and are shared amongst many components
- There is similar widespread usage for `ThemeData.highlightColor` (13)
- Other parameters can remain in the factory constructor (e.g. `ThemeData.fontFamily` and `ThemeData.fontFamilyFallback`) for convenience

## Component Theme Normalization

All of the existing themes have been normalized except for the following:

- [ ] `AppBarTheme`
- [ ] `BottomAppBarTheme`
- [ ] `InputDecorationTheme`
- [x] `CardTheme` #151914
- [x] `ChipTheme` #94179
- [x] `DialogTheme`#153982
- [x] `ListTileTheme` #91840
- [x] `TabBarTheme` #155476

<!---
\- |  Component  | - |  Component | - | Component
-- | -- | -- | -- | -- | --
🟠 | App bars: bottom | 🟠 | App bars: top | N/A | Backdrop
🟢 | Banners | 🟢 | Bottom Navigation | 🟢 | Buttons
  | Buttons: floating action | 🟠 | Cards | 🟢 | Chips
🟢 | Data tables | 🟠 | Dialogs | 🟢 | Dividers
N/A  | Image Lists | 🟠 | Lists | 🔴 | Menus
🟠 | Navigation Drawer | 🔵 | Pickers | 🟢 | Progress Indicators
🔵 | Checkboxes | 🔵 | Radio buttons | 🔵 | Switches
🟠 | Sheets: bottom | 🔵 | Sheets: side | 🟢 | Sliders
🟢 | Snackbars | 🔴 | Tabs | 🔴 | Text fields
  | Tooltips |   |   | ? |  Navigation Rail

N/A Currently there’s no Material library component.
🔵 There are no themes for the components in this category yet.
🔴 The theme support needs significant work to make it conformant.
🟠 The theme support needs a modest amount of work to make it conformant.
🟢 The theme support is conformant or very close.

--->