[XMLHttpRequest] Stop throwing for network error in async mode

LayoutTests/fast/files/workers/worker-apply-blob-url-to-xhr.html

Index: LayoutTests/fast/files/workers/worker-apply-blob-url-to-xhr.html
diff --git a/LayoutTests/fast/files/workers/worker-apply-blob-url-to-xhr.html b/LayoutTests/fast/files/workers/worker-apply-blob-url-to-xhr.html
index 2fb1d04a0212e577880375ece19caa81462b0fe2..7b440b8a1d884e6d7575cfdaa607ca170b47f1de 100644
--- a/LayoutTests/fast/files/workers/worker-apply-blob-url-to-xhr.html
+++ b/LayoutTests/fast/files/workers/worker-apply-blob-url-to-xhr.html
@@ -13,7 +13,7 @@ function log(message)
 function onInputFileChange()
 {
     var file = document.getElementById("file").files[0];
-    var worker = new Worker("resources/worker-apply-blob-url-to-xhr.js");
+    var worker = new Worker("../resources/apply-blob-url-to-xhr.js");
     worker.onmessage = function(event)
     {
         log(event.data);