[Fetch API] Put body members directly on Response/Request

LayoutTests/http/tests/serviceworker/resources/fetch-access-control-worker.js

 var port = undefined;
 var isTestTargetFetch = false;
 
 self.onmessage = function(e) {
   var message = e.data;
   if ('port' in message) {
     port = message.port;
   } else if (message.msg === 'START TEST CASE') {
     isTestTargetFetch = true;
     port.postMessage({msg: 'READY'});
@@ skipping 57 matching lines @@
       return;
     }
     event.respondWith(new Promise(function(resolve, reject) {
         try {
           var request = event.request;
           if (url) {
             request = new Request(url, init);
           } else if (!params['noChange']) {
             request = new Request(request, init);
           }
+          var response;
           fetch(request)
             .then(function(res) {
-                // Send the result to fetch-access-control.html.
-                port.postMessage({fetchResult: 'resolved',
-                                  hasBody: !!res.body,
-                                  headers: headersToArray(res.headers),
-                                  type: res.type,
-                                  originalURL: originalURL});
-                resolve(res);
+                response = res;
+                res.text()
+                  .then(function(body) {
+                      // Send the result to fetch-access-control.html.
+                      port.postMessage(
+                        {
+                          fetchResult: 'resolved',
+                          body: body,
+                          headers: headersToArray(response.headers),
+                          type: response.type,
+                          originalURL: originalURL
+                        });
+                      resolve(response);
+                    })
+                  .catch(function(e) {
+                      // Send the result to fetch-access-control.html.
+                      port.postMessage({fetchResult: 'error'});
+                      reject();
+                    });
               })
             .catch(function(e) {
                 // Send the result to fetch-access-control.html.
                 port.postMessage({fetchResult: 'rejected'});
                 reject();
               });
         } catch (e) {
           // Send the result to fetch-access-control.html.
           port.postMessage({fetchResult: 'error'});
           reject();
         }
       }));
   });