Enable the CORS preflight for sendBeacon()

third_party/WebKit/LayoutTests/http/tests/navigation/beacon-cross-origin.html

Index: third_party/WebKit/LayoutTests/http/tests/navigation/beacon-cross-origin.html
diff --git a/third_party/WebKit/LayoutTests/http/tests/navigation/beacon-cross-origin.html b/third_party/WebKit/LayoutTests/http/tests/navigation/beacon-cross-origin.html
index 4f959a4f82d85968e317245d93427a1614b47c9c..2ccf64ea190f300de4aae5c20434d447fa5eed66 100644
--- a/third_party/WebKit/LayoutTests/http/tests/navigation/beacon-cross-origin.html
+++ b/third_party/WebKit/LayoutTests/http/tests/navigation/beacon-cross-origin.html
@@ -15,7 +15,8 @@ function test() {
     }
 
     shouldBeTrue('navigator.sendBeacon("http://localhost:8000/navigation/resources/save-beacon.php?name=cross-origin", "CrossOrigin");');
-    var xhr = new XMLHttpRequest();
+  setTimeout(() => {
+  var xhr = new XMLHttpRequest();
     xhr.open("GET", "resources/check-beacon.php?name=cross-origin");
     xhr.onload = function () {
         var lines = xhr.responseText.split("\n");
@@ -28,6 +29,7 @@ function test() {
         finishJSTest();
     };
     xhr.send();
+  }, 1000);
 }
 </script>
 </head>