Use downloadToFile option when XHR downloads a Blob

LayoutTests/http/tests/xmlhttprequest/workers/resources/xmlhttprequest-response-type-blob-sync.js

Index: LayoutTests/http/tests/xmlhttprequest/workers/resources/xmlhttprequest-response-type-blob-sync.js
diff --git a/LayoutTests/http/tests/xmlhttprequest/workers/resources/xmlhttprequest-response-type-blob-sync.js b/LayoutTests/http/tests/xmlhttprequest/workers/resources/xmlhttprequest-response-type-blob-sync.js
new file mode 100644
index 0000000000000000000000000000000000000000..6a5a81b7d89ed7cae2cbafa16d680f43b956d302
--- /dev/null
+++ b/LayoutTests/http/tests/xmlhttprequest/workers/resources/xmlhttprequest-response-type-blob-sync.js
@@ -0,0 +1,27 @@
+importScripts("/js-test-resources/js-test.js");
+importScripts("worker-pre.js");
+
+function init() {
+    var global = self;
+
+    try {
+        global.req = new XMLHttpRequest;
+        req.responseType = "blob";
+        req.open("GET", "../../resources/get.txt", false);
+        req.send(null);
+
+        shouldBe("req.status", "200");
+        shouldBe("req.response.size", "4");
+        var reader = new FileReader();
+        reader.onload = function (evt) {
+            global.buffer = evt.target.result;
+            shouldBeEqualToString("buffer", "PASS");
+            testPassed("Sync XHR with responseType=\"blob\" succeeded");
+            finishJSTest();
+        };
+        reader.readAsText(req.response, "utf-8");
+    } catch (e) {
+        testFailed("failed to create XMLHttpRequest with exception: " + e.message);
+        finishJSTest();
+    }
+}