Remove dart backend

test/dart_codegen/expect/convert/chunked_conversion.dart

-part of dart.convert;
- typedef void _ChunkedConversionCallback<T>(T accumulated);
- abstract class ChunkedConversionSink<T> implements Sink<T> {ChunkedConversionSink();
- factory ChunkedConversionSink.withCallback(void callback(List<T> accumulated)) = _SimpleCallbackSink;
- void add(T chunk);
- void close();
-}
- class _SimpleCallbackSink<T> extends ChunkedConversionSink<T> {final _ChunkedConversionCallback<List<T>> _callback;
- final List<T> _accumulated = <T> [];
- _SimpleCallbackSink(this._callback);
- void add(T chunk) {
-_accumulated.add(chunk);
-}
- void close() {
-_callback(_accumulated);
-}
-}
- class _EventSinkAdapter<T> implements ChunkedConversionSink<T> {final EventSink<T> _sink;
- _EventSinkAdapter(this._sink);
- void add(T data) => _sink.add(data);
- void close() => _sink.close();
-}
- class _ConverterStreamEventSink<S, T> implements EventSink<S> {final EventSink<T> _eventSink;
- ChunkedConversionSink _chunkedSink;
- _ConverterStreamEventSink(Converter converter, EventSink<T> sink) : this._eventSink = sink, _chunkedSink = converter.startChunkedConversion(sink);
- void add(S o) => _chunkedSink.add(o);
- void addError(Object error, [StackTrace stackTrace]) {
-_eventSink.addError(error, stackTrace);
-}
- void close() => _chunkedSink.close();
-}