CSP: 'connect-src' should not cause exceptions.

third_party/WebKit/LayoutTests/external/wpt/content-security-policy/inside-worker/support/connect-src-allow.sub.js

 importScripts("{{location[server]}}/resources/testharness.js");
 importScripts("{{location[server]}}/content-security-policy/support/testharness-helper.js");
 
 // Same-origin
 async_test(t => {
   var url = "{{location[server]}}/content-security-policy/support/resource.py?same-origin-fetch";
   assert_no_csp_event_for_url(t, url);
 
   fetch(url)
     .then(t.step_func_done(r => assert_equals(r.status, 200)));
 }, "Same-origin 'fetch()' in " + self.location.protocol + self.location.search);
 
 async_test(t => {
   var url = "{{location[server]}}/content-security-policy/support/resource.py?same-origin-xhr";
   assert_no_csp_event_for_url(t, url);
 
   var xhr = new XMLHttpRequest();
-  try {
-    xhr.open("GET", url);
-    t.done();
-  } catch (e) {
-    assert_unreached();
-  }
+  xhr.open("GET", url);
+  xhr.onload = t.step_func_done();
+  xhr.onerror = t.unreached_func();
   xhr.send();
 }, "Same-origin XHR in " + self.location.protocol + self.location.search);
 
 // Cross-origin
 async_test(t => {
   var url = "http://{{domains[www]}}:{{ports[http][1]}}/content-security-policy/support/resource.py?cross-origin-fetch";
   assert_no_csp_event_for_url(t, url);
 
   fetch(url)
     .then(t.step_func_done(r => assert_equals(r.status, 200)));
 }, "Cross-origin 'fetch()' in " + self.location.protocol + self.location.search);
 
 async_test(t => {
   var url = "http://{{domains[www]}}:{{ports[http][1]}}/content-security-policy/support/resource.py?cross-origin-xhr";
   assert_no_csp_event_for_url(t, url);
 
   var xhr = new XMLHttpRequest();
-  try {
-    xhr.open("GET", url);
-    t.done();
-  } catch (e) {
-    assert_unreached();
-  }
+  xhr.open("GET", url);
+  xhr.onload = t.step_func_done();
+  xhr.onerror = t.unreached_func();
   xhr.send();
 }, "Cross-origin XHR in " + self.location.protocol + self.location.search);
 
 // Same-origin redirecting to cross-origin
 async_test(t => {
   var url = "{{location[server]}}/common/redirect-opt-in.py?status=307&location=http://{{domains[www]}}:{{ports[http][1]}}/content-security-policy/support/resource.py?cross-origin-fetch";
   assert_no_csp_event_for_url(t, url);
 
   fetch(url)
     .then(t.step_func_done(r => assert_equals(r.status, 200)));
 }, "Same-origin => cross-origin 'fetch()' in " + self.location.protocol + self.location.search);
 
 done();