As a maintainer of a flutter package that may contain references to assets, it is required that inside this package, assets should be loaded with package/<packageName> prefix in its key.

When testing code that loads these assets, we get an error after flutter 3.3.0

Steps to Reproduce

Added a simple code here in the issue and a more complete example here.

1. Checkout into flutter 3.0.0
2. Execute flutter test on the code sample or on the example package.
3. It will pass (as it should).
4. Checkout into flutter 3.3.0
5. Execute flutter test on the code sample or on the example package.
6. It will fail because it cant load the asset.

Expected results:

Tests should pass.

It should be consistent across versions since it was not listed as a breaking change.

Testing widgets with assets in packages can be a real hack if it is not possible to maintain the prefix during tests.

Actual results:

Tests fail.

// Package content file: lib/src/anything.dart

import 'package:flutter/widgets.dart';

/// Some Widget with an image
class SomeImageWidget extends StatelessWidget {
  /// Some Widget with an image
  const SomeImageWidget({super.key});

  @override
  Widget build(BuildContext context) {
    return Image.asset('packages/asset_bundle_bug/assets/pudim.jpg');
  }
}

// Test file: test/anything_test.dart

void main() {
  group('SomeImageWidget', () {
    testWidgets('can be pumped', (tester) async {
      await tester.pumpWidget(SomeImageWidget());
      await tester.pumpAndSettle();
      expect(true, true);
    });
  });
}

Possible context

This PR may have introduced the bug:
flutter/engine#32999
#103496