@Test
public void viewerExistsWhenPayloadIsPresent() {

  myTransportService.addFile(TEST_RESPONSE_PAYLOAD_ID, ByteString.copyFromUtf8("Dummy Content"));
  HttpData data = new HttpData.Builder(DEFAULT_DATA)
    .setResponseFields(RESPONSE_HEADERS)
    .setResponsePayloadId(TEST_RESPONSE_PAYLOAD_ID)
    .build();
  assertThat(findTab(myView, OverviewTabContent.class).findResponsePayloadViewer()).isNull();
  myView.setHttpData(data);
  assertThat(findTab(myView, OverviewTabContent.class).findResponsePayloadViewer()).isNotNull();
}