Deprecated ThemeData buttonColor (#82196)

packages/flutter/lib/src/material/button.dart

@@ -29,7 +29,7 @@ import 'theme_data.dart';
 /// TextButton, ElevatedButton, and OutlinedButton respectively.
 /// ButtonTheme has been replaced by TextButtonTheme,
 /// ElevatedButtonTheme, and OutlinedButtonTheme. The original classes
-/// will be deprecated soon, please migrate code that uses them.
+/// have been deprecated, please migrate code that uses them.
 /// There's a detailed migration guide for the new button and button
 /// theme classes in
 /// [flutter.dev/go/material-button-migration-guide](https://flutter.dev/go/material-button-migration-guide).

packages/flutter/lib/src/material/button_theme.dart

@@ -55,8 +55,8 @@ enum ButtonBarLayoutBehavior {
 /// Please use one or more of the new buttons and their themes
 /// instead: [TextButton] and [TextButtonTheme], [ElevatedButton] and
 /// [ElevatedButtonTheme], [OutlinedButton] and
-/// [OutlinedButtonTheme]. The original classes will be deprecated
-/// soon, please migrate code that uses them.  There's a detailed
+/// [OutlinedButtonTheme]. The original classes have been deprecated,
+/// please migrate code that uses them.  There's a detailed
 /// migration guide for the new button and button theme classes in
 /// [flutter.dev/go/material-button-migration-guide](https://flutter.dev/go/material-button-migration-guide).
 ///
@@ -179,7 +179,7 @@ class ButtonTheme extends InheritedTheme {
 /// TextButton, ElevatedButton, and OutlinedButton respectively.
 /// ButtonTheme has been replaced by TextButtonTheme,
 /// ElevatedButtonTheme, and OutlinedButtonTheme. The original classes
-/// will be deprecated soon, please migrate code that uses them.
+/// have been deprecated, please migrate code that uses them.
 /// There's a detailed migration guide for the new button and button
 /// theme classes in
 /// [flutter.dev/go/material-button-migration-guide](https://flutter.dev/go/material-button-migration-guide).

packages/flutter/lib/src/material/material_button.dart

@@ -28,7 +28,7 @@ import 'theme_data.dart';
 /// new widgets can be customized by specifying a [ButtonStyle]
 /// or by creating a one-off style using a `styleFrom` method like
 /// [TextButton.styleFrom]. The original button classes
-/// will be deprecated soon, please migrate code that uses them.
+/// have been deprecated, please migrate code that uses them.
 /// There's a detailed migration guide for the new button and button
 /// theme classes in
 /// [flutter.dev/go/material-button-migration-guide](https://flutter.dev/go/material-button-migration-guide).
@@ -177,8 +177,6 @@ class MaterialButton extends StatelessWidget {
   /// The button's fill color, displayed by its [Material], while it
   /// is in its default (unpressed, [enabled]) state.
   ///
-  /// The default fill color is the theme's button color, [ThemeData.buttonColor].
-  ///
   /// See also:
   ///
   ///  * [disabledColor] - the fill color of the button when the button is disabled.

packages/flutter/lib/src/material/theme_data.dart

@@ -248,6 +248,10 @@ class ThemeData with Diagnosticable {
     Color? selectedRowColor,
     Color? unselectedWidgetColor,
     Color? disabledColor,
+    @Deprecated(
+      'No longer used by the framework, please remove any reference to it. '
+      'This feature was deprecated after v2.3.0-0.2.pre.',
+    )
     Color? buttonColor,
     ButtonThemeData? buttonTheme,
     ToggleButtonsThemeData? toggleButtonsTheme,
@@ -585,6 +589,10 @@ class ThemeData with Diagnosticable {
     required this.unselectedWidgetColor,
     required this.disabledColor,
     required this.buttonTheme,
+    @Deprecated(
+      'No longer used by the framework, please remove any reference to it. '
+      'This feature was deprecated after v2.3.0-0.2.pre.',
+    )
     required this.buttonColor,
     required this.toggleButtonsTheme,
     required this.secondaryHeaderColor,
@@ -991,6 +999,10 @@ class ThemeData with Diagnosticable {
   final ToggleButtonsThemeData toggleButtonsTheme;
 
   /// The default fill color of the [Material] used in [RaisedButton]s.
+  @Deprecated(
+    'No longer used by the framework, please remove any reference to it. '
+    'This feature was deprecated after v2.3.0-0.2.pre.',
+  )
   final Color buttonColor;
 
   /// The color of the header of a [PaginatedDataTable] when there are selected rows.
@@ -1336,6 +1348,10 @@ class ThemeData with Diagnosticable {
     Color? disabledColor,
     ButtonThemeData? buttonTheme,
     ToggleButtonsThemeData? toggleButtonsTheme,
+    @Deprecated(
+      'No longer used by the framework, please remove any reference to it. '
+      'This feature was deprecated after v2.3.0-0.2.pre.',
+    )
     Color? buttonColor,
     Color? secondaryHeaderColor,
     @Deprecated(

packages/flutter/test/material/snack_bar_test.dart

@@ -706,7 +706,6 @@ void main() {
       disabledColor: Colors.black,
       buttonTheme: const ButtonThemeData(colorScheme: ColorScheme.dark()),
       toggleButtonsTheme: const ToggleButtonsThemeData(textStyle: TextStyle(color: Colors.black)),
-      buttonColor: Colors.black,
       secondaryHeaderColor: Colors.black,
       textSelectionColor: Colors.black,
       cursorColor: Colors.black,