Import w3c tests for the service workers

third_party/WebKit/LayoutTests/imported/wpt/service-workers/service-worker/resources/fetch-event-redirect-iframe.html

+<script>
+window.addEventListener('message', function(evt) {
+  var port = evt.ports[0];
+  var data = evt.data;
+  fetch(new Request(data.url, data.request_init)).then(function(response) {
+    if (data.request_init.mode === 'no-cors' && data.redirect_dest != 'same-origin') {
+      if (response.type === data.expected_type &&
+          (response.type === 'opaque' || response.type === 'opaqueredirect') &&
+          response.redirected === data.expected_redirected) {
+        return {result: 'success', detail: ''};
+      } else {
+        return {result: 'failure',
+                detail: 'expected type ' + data.expected_type +
+                        ', expected redirected ' + data.expected_redirected +
+                        ' response'};
+      }
+    }
+    return response.json();
+  }).then(function(body) {
+    port.postMessage({result: body.result, detail: body.detail});
+  }).catch(function(e) {
+    port.postMessage({result: 'reject', detail: e.toString()});
+  });
+});
+</script>