Rework EventSource CORS tests to be usable from Workers.

LayoutTests/http/tests/eventsource/script-tests/eventsource-cors-non-http.js

Index: LayoutTests/http/tests/eventsource/script-tests/eventsource-cors-non-http.js
diff --git a/LayoutTests/http/tests/eventsource/script-tests/eventsource-cors-non-http.js b/LayoutTests/http/tests/eventsource/script-tests/eventsource-cors-non-http.js
new file mode 100644
index 0000000000000000000000000000000000000000..9177aba8a7c973156023e5e00551f2088475597a
--- /dev/null
+++ b/LayoutTests/http/tests/eventsource/script-tests/eventsource-cors-non-http.js
@@ -0,0 +1,18 @@
+if (self.importScripts)
+    importScripts("/js-test-resources/js-test.js");
+
+description("Test EventSource with non-HTTP protocol schemes in the URL.");
+
+self.jsTestIsAsync = true;
+
+var es, count = 0;
+
+new EventSource("ftp://127.0.0.1").onerror =
+new EventSource("file:///etc/motd").onerror =
+new EventSource("localhost:8080/").onerror =
+new EventSource("tel:1234").onerror = function () {
+    es = this;
+    shouldBe("es.readyState", "EventSource.CLOSED");
+    if (count++ == 3)
+        finishJSTest();
+};