GrpcClientResponse extends RpcClientResponse implements GrpcResponse { @Override public Metadata trailers() { return trailers; } GrpcClientResponse(GrpcClientRequest request, Metadata headers, Status status,
      Metadata trailers); @Override Status unwrap(); @Override GrpcClientRequest request(); @Override @Nullable Throwable error(); @Override @Nullable String errorCode(); @Override Metadata headers(); @Override Status status(); @Override Metadata trailers();  }
@Test public void trailers() { assertThat(response.trailers()).isSameAs(trailers); }