title: Fetch Promise resolves but does not continue
body: <p>I am attempting to use fetch as follows</p>
  
  <pre><code>export function* loadData() {
    console.log("Saga: Loading Data...");
    try {
      const response = yield call(request, requestURL,
      { method: 'GET', credentials: 'include', headers: {
      'Content-Type': 'application/json', }  });
      // Nothing past this point is ever touched
      if (response.success) {
       console.log("SUCCESS!!!!");
       ...
  
  export default function request(url, options) {
    return fetch(url, options)
      .then(checkStatus)
      .then(parseJSON);
  }
  </code></pre>
  
  <p>CheckStatus confirms a successful status on the data</p>
  
  <pre><code>function parseJSON(response) {
    if (response.status === 204 || response.status === 205) {
      return null;
    }
    var responseClone = response.clone();
    console.log(responseClone.json());
    return response.json();
  }
  </code></pre>
  
  <p>Not enough rep to post a screenshot of the clone output, but essentially chrome dev outputs</p>
  
  <pre><code>SAGA: Loading Data...
  [[PromiseStatus]]:"resolved"
  [[PromiseValue]]:Object
  </code></pre>
  
  <p>And the object contains all the data I need, the code just wont continue past that response call. </p>