SchemaCoder cannot encode row with null value in array

import com.google.common.io.ByteStreams;
import org.apache.beam.sdk.schemas.Schema;
import org.apache.beam.sdk.schemas.SchemaCoder;
import org.apache.beam.sdk.values.Row;
import java.io.IOException;
import java.util.Collections;

public class Main {
    public static void main(String[] args) throws IOException {
        Schema schema = Schema.builder()
                .addField("a", Schema.FieldType.array(Schema.FieldType.INT32, true))
                .build();

        Row row = Row.withSchema(schema).addValue(Collections.singletonList(null)).build();

        SchemaCoder.of(schema).encode(row, ByteStreams.nullOutputStream());
    }
}