Fix a bug in origin header generation for CORS preflight in extensions

third_party/WebKit/LayoutTests/http/tests/xmlhttprequest/resources/access-control-origin-header-in-isolated-world.php

Index: third_party/WebKit/LayoutTests/http/tests/xmlhttprequest/resources/access-control-origin-header-in-isolated-world.php
diff --git a/third_party/WebKit/LayoutTests/http/tests/xmlhttprequest/resources/access-control-origin-header-in-isolated-world.php b/third_party/WebKit/LayoutTests/http/tests/xmlhttprequest/resources/access-control-origin-header-in-isolated-world.php
new file mode 100644
index 0000000000000000000000000000000000000000..0556700a5fa44196b1637b0a5c6eaad94318da04
--- /dev/null
+++ b/third_party/WebKit/LayoutTests/http/tests/xmlhttprequest/resources/access-control-origin-header-in-isolated-world.php
@@ -0,0 +1,13 @@
+<?php
+if ($_SERVER["HTTP_ORIGIN"] == "http://example.com") {
+  header("Access-Control-Allow-Origin: http://example.com");
+
+  if ($_SERVER["REQUEST_METHOD"] == "OPTIONS") {
+    header("Access-Control-Allow-Headers: X-Custom-Header");
+  } else {
+    print $_SERVER["HTTP_X_CUSTOM_HEADER"];
+  }
+} else {
+  header("HTTP/1.1 400");
+}
+?>