Convert Service Worker layout tests to W3C testharness-style tests

LayoutTests/http/tests/serviceworker/resources/postmessage-worker.js

Index: LayoutTests/http/tests/serviceworker/resources/postmessage-worker.js
diff --git a/LayoutTests/http/tests/serviceworker/postmessage-worker.js b/LayoutTests/http/tests/serviceworker/resources/postmessage-worker.js
similarity index 78%
rename from LayoutTests/http/tests/serviceworker/postmessage-worker.js
rename to LayoutTests/http/tests/serviceworker/resources/postmessage-worker.js
index 48fda992363dbde6ef3aaa18d0ff397abab818f1..83cda3b7e23573408c5c106846d779b05c2ddad8 100644
--- a/LayoutTests/http/tests/serviceworker/postmessage-worker.js
+++ b/LayoutTests/http/tests/serviceworker/resources/postmessage-worker.js
@@ -12,8 +12,8 @@ self.onmessage = function(e) {
 self.addEventListener('message', function(e) {
     var message = e.data;
     if ('value' in message) {
-        port.postMessage("Acking value: " + message.value);
+        port.postMessage('Acking value: ' + message.value);
     } else if ('done' in message) {
-        port.postMessage("quit");
+        port.postMessage('quit');
     }
 });