Allow sites to enable 'window.onerror' handlers for cross-domain scripts.

LayoutTests/http/tests/security/resources/cors-script.php

Index: LayoutTests/http/tests/security/resources/cors-script.php
diff --git a/LayoutTests/http/tests/security/resources/cors-script.php b/LayoutTests/http/tests/security/resources/cors-script.php
index 298acf1166aa5c0a83057f9eabb46e2f6481d202..61f3de82f214745c2ecd171ef61ddbf3bb3b4128 100644
--- a/LayoutTests/http/tests/security/resources/cors-script.php
+++ b/LayoutTests/http/tests/security/resources/cors-script.php
@@ -1,5 +1,7 @@
 <?php
-header("Access-Control-Allow-Origin: http://127.0.0.1:8000");
+if (strtolower($_GET["cors"]) != "false") {
+    header("Access-Control-Allow-Origin: http://127.0.0.1:8000");
+}
 header("Content-Type: application/javascript");
 if (strtolower($_GET["fail"]) == "true")
     echo "throw({toString: function(){ return 'SomeError' }});";