Enable the CORS preflight for sendBeacon()

third_party/WebKit/LayoutTests/http/tests/navigation/resources/save-beacon.php

Index: third_party/WebKit/LayoutTests/http/tests/navigation/resources/save-beacon.php
diff --git a/third_party/WebKit/LayoutTests/http/tests/navigation/resources/save-beacon.php b/third_party/WebKit/LayoutTests/http/tests/navigation/resources/save-beacon.php
index 1888c9329cc5bdbd380cf21a39a513310e89488e..e564a7e8d044b684b2fa29efc0666e229fa26aa7 100644
--- a/third_party/WebKit/LayoutTests/http/tests/navigation/resources/save-beacon.php
+++ b/third_party/WebKit/LayoutTests/http/tests/navigation/resources/save-beacon.php
@@ -1,6 +1,14 @@
 <?php
 require_once '../../resources/portabilityLayer.php';
 
+if ($_SERVER["REQUEST_METHOD"] == "OPTIONS") {
+   header("Access-Control-Allow-Origin: http://127.0.0.1:8000");
+   header("Access-Control-Allow-Credentials: true");
+   header("Access-Control-Allow-Method: post");
+   header("Access-Control-Allow-Headers: content-type,cache-control");
+   exit();
+}
+
 function prettify($name) {
    return str_replace(' ', '-', ucwords(str_replace('_', ' ', str_replace('http_', '', strtolower($name)))));
 }