read method
A generated file (isGeneratedAsset) is read with
loadRevalidatedAsset, so on the web a cached copy from an older
deploy is never paired with newer code โ A4.18.
A key the bundle does not hold is an AssetNotFoundException naming it, with
the platform's own FlutterError as its cause โ readiness review
ยง2.2.6 โ so a caller that catches the engine's root catches this too.
Implementation
@override
Future<Uint8List> read(AssetRead request) => _load(assetPath);