Fix MaterialStateBorderSide lerp in the Checkbox and chips

[TahaTesser]

fixes Checkbox and Chips side with MaterialStateBorderSide doesn't lerp in their theme

Code sample

expand to view the code sample

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

void main() {
  testWidgets('test', (WidgetTester tester) async {
    late ColorScheme colorScheme;

    Widget buildCheckbox({required Color seedColor}) {
      colorScheme = ColorScheme.fromSeed(seedColor: seedColor);
      return MaterialApp(
        theme: ThemeData(
          colorScheme: colorScheme,
          checkboxTheme: CheckboxThemeData(
            side: MaterialStateBorderSide.resolveWith(
                (Set<MaterialState> states) {
              return BorderSide(
                color: colorScheme.primary,
                width: 4.0,
              );
            }),
          ),
        ),
        home: Scaffold(
          body: Center(
            child: Checkbox(
              value: false,
              onChanged: (_) {},
            ),
          ),
        ),
      );
    }

    await tester.pumpWidget(buildCheckbox(seedColor: Colors.red));
    await tester.pumpAndSettle();

    RenderBox getCheckboxRenderer() {
      return tester.renderObject<RenderBox>(find.byType(Checkbox));
    }

    expect(getCheckboxRenderer(), paints..drrect(color: colorScheme.primary));

    await Future<void>.delayed(const Duration(seconds: 3));

    await tester.pumpWidget(buildCheckbox(seedColor: Colors.blue));
    await tester.pump();

    await Future<void>.delayed(const Duration(seconds: 3));

    expect(getCheckboxRenderer(), paints..drrect(color: colorScheme.primary));
  });
}

Before	After

Pre-launch Checklist

• I read the Contributor Guide and followed the process outlined there for submitting PRs.
• I read the Tree Hygiene wiki page, which explains my responsibilities.
• I read and followed the Flutter Style Guide, including Features we expect every widget to implement.
• I signed the CLA.
• I listed at least one issue that this PR fixes in the description above.
• I updated/added relevant documentation (doc comments with ///).
• I added new tests to check the change I am making, or this PR is test-exempt.
• I followed the breaking change policy and added Data Driven Fixes where supported.
• All existing and new tests are passing.

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[guidezpl]

NICE