Fix cancelButtonStyle & confirmButtonStyle properties from TimePickerTheme aren't working (#132843)

fixes [`TimePickerThemeData` action buttons styles aren't working](flutter/flutter#132760)

### Code sample

<details> 
<summary>expand to view the code sample</summary> 

```dart
import 'package:flutter/material.dart';

void main() => runApp(const MyApp());

class MyApp extends StatelessWidget {
  const MyApp({super.key});

  @OverRide
  Widget build(BuildContext context) {
    return MaterialApp(
      debugShowCheckedModeBanner: false,
      theme: ThemeData(
        useMaterial3: true,
        timePickerTheme: TimePickerThemeData(
          cancelButtonStyle: TextButton.styleFrom(
            shape: const RoundedRectangleBorder(
              borderRadius: BorderRadius.all(Radius.circular(4)),
              side: BorderSide(color: Colors.red),
            ),
            backgroundColor: Colors.white,
            foregroundColor: Colors.red,
            elevation: 3,
            shadowColor: Colors.red,
          ),
          confirmButtonStyle: TextButton.styleFrom(
            shape: const RoundedRectangleBorder(
              borderRadius: BorderRadius.all(Radius.circular(4)),
            ),
            backgroundColor: Colors.green[700],
            foregroundColor: Colors.white,
            elevation: 3,
            shadowColor: Colors.green[700],
          ),
        ),
      ),
      home: const Example(),
    );
  }
}

class Example extends StatelessWidget {
  const Example({super.key});

  @OverRide
  Widget build(BuildContext context) {
    return Scaffold(
      body: Center(
        child: TimePickerDialog(initialTime: TimeOfDay.now()),
      ),
    );
  }
}

``` 

</details>

### Before (action buttons don't use the style from the `TimePickerTheme`)

![Screenshot 2023-08-18 at 14 57 37](https://github.com/flutter/flutter/assets/48603081/c95160e2-76a2-4bb5-84e0-3731fce19c0b)

### After (action buttons use the style from the `TimePickerTheme`)

![Screenshot 2023-08-18 at 14 57 18](https://github.com/flutter/flutter/assets/48603081/422d348a-bee2-4696-8d9a-5fce56191aaa)

Author: TahaTesser

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

@@ -2384,13 +2384,15 @@ class _TimePickerDialogState extends State<TimePickerDialog> with RestorationMix
                 overflowAlignment: OverflowBarAlignment.end,
                 children: <Widget>[
                   TextButton(
+                    style: pickerTheme.cancelButtonStyle ?? defaultTheme.cancelButtonStyle,
                     onPressed: _handleCancel,
                     child: Text(widget.cancelText ??
                         (theme.useMaterial3
                             ? localizations.cancelButtonLabel
                             : localizations.cancelButtonLabel.toUpperCase())),
                   ),
                   TextButton(
+                    style: pickerTheme.confirmButtonStyle ?? defaultTheme.confirmButtonStyle,
                     onPressed: _handleOk,
                     child: Text(widget.confirmText ?? localizations.okButtonLabel),
                   ),

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

@@ -72,7 +72,7 @@ class TimePickerThemeData with Diagnosticable {
   /// The style of the cancel button of a [TimePickerDialog].
   final ButtonStyle? cancelButtonStyle;
 
-  /// The style of the conform (OK) button of a [TimePickerDialog].
+  /// The style of the confirm (OK) button of a [TimePickerDialog].
   final ButtonStyle? confirmButtonStyle;
 
   /// The color and weight of the day period's outline.

packages/flutter/test/material/time_picker_theme_test.dart

@@ -20,22 +20,28 @@ void main() {
   test('TimePickerThemeData null fields by default', () {
     const TimePickerThemeData timePickerTheme = TimePickerThemeData();
     expect(timePickerTheme.backgroundColor, null);
-    expect(timePickerTheme.hourMinuteTextColor, null);
-    expect(timePickerTheme.hourMinuteColor, null);
-    expect(timePickerTheme.dayPeriodTextColor, null);
+    expect(timePickerTheme.cancelButtonStyle, null);
+    expect(timePickerTheme.confirmButtonStyle, null);
+    expect(timePickerTheme.dayPeriodBorderSide, null);
     expect(timePickerTheme.dayPeriodColor, null);
-    expect(timePickerTheme.dialHandColor, null);
+    expect(timePickerTheme.dayPeriodShape, null);
+    expect(timePickerTheme.dayPeriodTextColor, null);
+    expect(timePickerTheme.dayPeriodTextStyle, null);
     expect(timePickerTheme.dialBackgroundColor, null);
+    expect(timePickerTheme.dialHandColor, null);
     expect(timePickerTheme.dialTextColor, null);
+    expect(timePickerTheme.dialTextStyle, null);
+    expect(timePickerTheme.elevation, null);
     expect(timePickerTheme.entryModeIconColor, null);
-    expect(timePickerTheme.hourMinuteTextStyle, null);
-    expect(timePickerTheme.dayPeriodTextStyle, null);
     expect(timePickerTheme.helpTextStyle, null);
-    expect(timePickerTheme.shape, null);
+    expect(timePickerTheme.hourMinuteColor, null);
     expect(timePickerTheme.hourMinuteShape, null);
-    expect(timePickerTheme.dayPeriodShape, null);
-    expect(timePickerTheme.dayPeriodBorderSide, null);
+    expect(timePickerTheme.hourMinuteTextColor, null);
+    expect(timePickerTheme.hourMinuteTextStyle, null);
     expect(timePickerTheme.inputDecorationTheme, null);
+    expect(timePickerTheme.entryModeIconColor, null);
+    expect(timePickerTheme.padding, null);
+    expect(timePickerTheme.shape, null);
   });
 
   testWidgets('Default TimePickerThemeData debugFillProperties', (WidgetTester tester) async {
@@ -53,47 +59,67 @@ void main() {
   testWidgets('TimePickerThemeData implements debugFillProperties', (WidgetTester tester) async {
     final DiagnosticPropertiesBuilder builder = DiagnosticPropertiesBuilder();
     const TimePickerThemeData(
-      backgroundColor: Color(0xFFFFFFFF),
-      hourMinuteTextColor: Color(0xFFFFFFFF),
-      hourMinuteColor: Color(0xFFFFFFFF),
-      dayPeriodTextColor: Color(0xFFFFFFFF),
-      dayPeriodColor: Color(0xFFFFFFFF),
-      dialHandColor: Color(0xFFFFFFFF),
-      dialBackgroundColor: Color(0xFFFFFFFF),
-      dialTextColor: Color(0xFFFFFFFF),
-      entryModeIconColor: Color(0xFFFFFFFF),
-      hourMinuteTextStyle: TextStyle(),
-      dayPeriodTextStyle: TextStyle(),
-      helpTextStyle: TextStyle(),
-      shape: RoundedRectangleBorder(),
-      hourMinuteShape: RoundedRectangleBorder(),
-      dayPeriodShape: RoundedRectangleBorder(),
-      dayPeriodBorderSide: BorderSide(),
+      backgroundColor: Color(0xfffffff0),
+      cancelButtonStyle: ButtonStyle(foregroundColor: MaterialStatePropertyAll<Color>(Color(0xfffffff1))),
+      confirmButtonStyle: ButtonStyle(foregroundColor: MaterialStatePropertyAll<Color>(Color(0xfffffff2))),
+      dayPeriodBorderSide: BorderSide(color: Color(0xfffffff3)),
+      dayPeriodColor: Color(0xfffffff4),
+      dayPeriodShape: RoundedRectangleBorder(
+        side: BorderSide(color: Color(0xfffffff5)),
+      ),
+      dayPeriodTextColor: Color(0xfffffff6),
+      dayPeriodTextStyle: TextStyle(color: Color(0xfffffff7)),
+      dialBackgroundColor: Color(0xfffffff8),
+      dialHandColor: Color(0xfffffff9),
+      dialTextColor: Color(0xfffffffa),
+      dialTextStyle: TextStyle(color: Color(0xfffffffb)),
+      elevation: 1.0,
+      entryModeIconColor: Color(0xfffffffc),
+      helpTextStyle: TextStyle(color: Color(0xfffffffd)),
+      hourMinuteColor: Color(0xfffffffe),
+      hourMinuteShape: RoundedRectangleBorder(
+        side: BorderSide(color: Color(0xffffffff)),
+      ),
+      hourMinuteTextColor: Color(0xfffffff0),
+      hourMinuteTextStyle: TextStyle(color: Color(0xfffffff1)),
+      inputDecorationTheme: InputDecorationTheme(
+        labelStyle: TextStyle(color: Color(0xfffffff2)),
+      ),
+      padding: EdgeInsets.all(1.0),
+      shape: RoundedRectangleBorder(
+        side: BorderSide(color: Color(0xfffffff3)),
+      ),
     ).debugFillProperties(builder);
 
     final List<String> description = builder.properties
         .where((DiagnosticsNode node) => !node.isFiltered(DiagnosticLevel.info))
         .map((DiagnosticsNode node) => node.toString())
         .toList();
 
-    expect(description, <String>[
-      'backgroundColor: Color(0xffffffff)',
-      'dayPeriodBorderSide: BorderSide',
-      'dayPeriodColor: Color(0xffffffff)',
-      'dayPeriodShape: RoundedRectangleBorder(BorderSide(width: 0.0, style: none), BorderRadius.zero)',
-      'dayPeriodTextColor: Color(0xffffffff)',
-      'dayPeriodTextStyle: TextStyle(<all styles inherited>)',
-      'dialBackgroundColor: Color(0xffffffff)',
-      'dialHandColor: Color(0xffffffff)',
-      'dialTextColor: Color(0xffffffff)',
-      'entryModeIconColor: Color(0xffffffff)',
-      'helpTextStyle: TextStyle(<all styles inherited>)',
-      'hourMinuteColor: Color(0xffffffff)',
-      'hourMinuteShape: RoundedRectangleBorder(BorderSide(width: 0.0, style: none), BorderRadius.zero)',
-      'hourMinuteTextColor: Color(0xffffffff)',
-      'hourMinuteTextStyle: TextStyle(<all styles inherited>)',
-      'shape: RoundedRectangleBorder(BorderSide(width: 0.0, style: none), BorderRadius.zero)'
-    ]);
+    expect(description, equalsIgnoringHashCodes(<String>[
+      'backgroundColor: Color(0xfffffff0)',
+      'cancelButtonStyle: ButtonStyle#00000(foregroundColor: MaterialStatePropertyAll(Color(0xfffffff1)))',
+      'confirmButtonStyle: ButtonStyle#00000(foregroundColor: MaterialStatePropertyAll(Color(0xfffffff2)))',
+      'dayPeriodBorderSide: BorderSide(color: Color(0xfffffff3))',
+      'dayPeriodColor: Color(0xfffffff4)',
+      'dayPeriodShape: RoundedRectangleBorder(BorderSide(color: Color(0xfffffff5)), BorderRadius.zero)',
+      'dayPeriodTextColor: Color(0xfffffff6)',
+      'dayPeriodTextStyle: TextStyle(inherit: true, color: Color(0xfffffff7))',
+      'dialBackgroundColor: Color(0xfffffff8)',
+      'dialHandColor: Color(0xfffffff9)',
+      'dialTextColor: Color(0xfffffffa)',
+      'dialTextStyle: TextStyle(inherit: true, color: Color(0xfffffffb))',
+      'elevation: 1.0',
+      'entryModeIconColor: Color(0xfffffffc)',
+      'helpTextStyle: TextStyle(inherit: true, color: Color(0xfffffffd))',
+      'hourMinuteColor: Color(0xfffffffe)',
+      'hourMinuteShape: RoundedRectangleBorder(BorderSide(color: Color(0xffffffff)), BorderRadius.zero)',
+      'hourMinuteTextColor: Color(0xfffffff0)',
+      'hourMinuteTextStyle: TextStyle(inherit: true, color: Color(0xfffffff1))',
+      'inputDecorationTheme: InputDecorationTheme#ff861(labelStyle: TextStyle(inherit: true, color: Color(0xfffffff2)))',
+      'padding: EdgeInsets.all(1.0)',
+      'shape: RoundedRectangleBorder(BorderSide(color: Color(0xfffffff3)), BorderRadius.zero)'
+    ]));
   });
 
   testWidgets('Material2 - Passing no TimePickerThemeData uses defaults', (WidgetTester tester) async {
@@ -221,6 +247,12 @@ void main() {
       entryModeIconButton.color,
       defaultTheme.colorScheme.onSurface.withOpacity(0.6),
     );
+
+    final ButtonStyle cancelButtonStyle = _actionButtonStyle(tester, 'CANCEL');
+    expect(cancelButtonStyle.toString(), equalsIgnoringHashCodes(TextButton.styleFrom().toString()));
+
+    final ButtonStyle confirmButtonStyle = _actionButtonStyle(tester, 'OK');
+    expect(confirmButtonStyle.toString(), equalsIgnoringHashCodes(TextButton.styleFrom().toString()));
   });
 
   testWidgets('Material3 - Passing no TimePickerThemeData uses defaults', (WidgetTester tester) async {
@@ -363,6 +395,12 @@ void main() {
 
     final IconButton entryModeIconButton = _entryModeIconButton(tester);
     expect(entryModeIconButton.color, null);
+
+    final ButtonStyle cancelButtonStyle = _actionButtonStyle(tester, 'Cancel');
+    expect(cancelButtonStyle.toString(), equalsIgnoringHashCodes(TextButton.styleFrom().toString()));
+
+    final ButtonStyle confirmButtonStyle = _actionButtonStyle(tester, 'OK');
+    expect(confirmButtonStyle.toString(), equalsIgnoringHashCodes(TextButton.styleFrom().toString()));
   });
 
   testWidgets('Material2 - Passing no TimePickerThemeData uses defaults - input mode', (WidgetTester tester) async {
@@ -399,6 +437,12 @@ void main() {
       Typography.material2014().englishLike.displayMedium!
         .merge(defaultTheme.textTheme.displayMedium!.copyWith(color: defaultTheme.colorScheme.onSurface.withOpacity(0.36)))
     );
+
+    final ButtonStyle cancelButtonStyle = _actionButtonStyle(tester, 'CANCEL');
+    expect(cancelButtonStyle.toString(), equalsIgnoringHashCodes(TextButton.styleFrom().toString()));
+
+    final ButtonStyle confirmButtonStyle= _actionButtonStyle(tester, 'OK');
+    expect(confirmButtonStyle.toString(), equalsIgnoringHashCodes(TextButton.styleFrom().toString()));
   });
 
   testWidgets('Material3 - Passing no TimePickerThemeData uses defaults - input mode', (WidgetTester tester) async {
@@ -438,6 +482,12 @@ void main() {
       hourDecoration.hintStyle,
       TextStyle(color: defaultTheme.colorScheme.onSurface.withOpacity(0.36))
     );
+
+    final ButtonStyle cancelButtonStyle = _actionButtonStyle(tester, 'Cancel');
+    expect(cancelButtonStyle.toString(), equalsIgnoringHashCodes(TextButton.styleFrom().toString()));
+
+    final ButtonStyle confirmButtonStyle = _actionButtonStyle(tester, 'OK');
+    expect(confirmButtonStyle.toString(), equalsIgnoringHashCodes(TextButton.styleFrom().toString()));
   });
 
   testWidgets('Material2 - Time picker uses values from TimePickerThemeData', (WidgetTester tester) async {
@@ -555,6 +605,12 @@ void main() {
       entryModeIconButton.color,
       timePickerTheme.entryModeIconColor,
     );
+
+    final ButtonStyle cancelButtonStyle = _actionButtonStyle(tester, 'CANCEL');
+    expect(cancelButtonStyle.toString(), equalsIgnoringHashCodes(timePickerTheme.cancelButtonStyle.toString()));
+
+    final ButtonStyle confirmButtonStyle = _actionButtonStyle(tester, 'OK');
+    expect(confirmButtonStyle.toString(), equalsIgnoringHashCodes(timePickerTheme.confirmButtonStyle.toString()));
   });
 
   testWidgets('Material3 - Time picker uses values from TimePickerThemeData', (WidgetTester tester) async {
@@ -672,6 +728,12 @@ void main() {
 
     final IconButton entryModeIconButton = _entryModeIconButton(tester);
     expect(entryModeIconButton.color, null);
+
+    final ButtonStyle cancelButtonStyle = _actionButtonStyle(tester, 'Cancel');
+    expect(cancelButtonStyle.toString(), equalsIgnoringHashCodes(timePickerTheme.cancelButtonStyle.toString()));
+
+    final ButtonStyle confirmButtonStyle = _actionButtonStyle(tester, 'OK');
+    expect(confirmButtonStyle.toString(), equalsIgnoringHashCodes(timePickerTheme.confirmButtonStyle.toString()));
   });
 
   testWidgets('Time picker uses values from TimePickerThemeData with InputDecorationTheme - input mode', (WidgetTester tester) async {
@@ -713,6 +775,8 @@ TimePickerThemeData _timePickerTheme({bool includeInputDecoration = false}) {
   final MaterialStateColor materialStateColor = MaterialStateColor.resolveWith(getColor);
   return TimePickerThemeData(
     backgroundColor: Colors.orange,
+    cancelButtonStyle: TextButton.styleFrom(primary: Colors.red),
+    confirmButtonStyle: TextButton.styleFrom(primary: Colors.green),
     hourMinuteTextColor: materialStateColor,
     hourMinuteColor: materialStateColor,
     dayPeriodTextColor: materialStateColor,
@@ -807,3 +871,7 @@ final Finder findDialPaint = find.descendant(
   of: find.byWidgetPredicate((Widget w) => '${w.runtimeType}' == '_Dial'),
   matching: find.byWidgetPredicate((Widget w) => w is CustomPaint),
 );
+
+ButtonStyle _actionButtonStyle(WidgetTester tester, String text) {
+  return tester.widget<TextButton>(find.widgetWithText(TextButton, text)).style!;
+}