ServiceWorker: Enable ServiceWorkerRegistration and update layout tests

LayoutTests/http/tests/serviceworker/chromium/service-worker-gc.html

Index: LayoutTests/http/tests/serviceworker/chromium/service-worker-gc.html
diff --git a/LayoutTests/http/tests/serviceworker/chromium/service-worker-gc.html b/LayoutTests/http/tests/serviceworker/chromium/service-worker-gc.html
index 18e09f603fb74b31cb7594bc4af669a5cb0de62f..3b3def52b9aae798c5d6305ab53821fce2c2c57a 100644
--- a/LayoutTests/http/tests/serviceworker/chromium/service-worker-gc.html
+++ b/LayoutTests/http/tests/serviceworker/chromium/service-worker-gc.html
@@ -3,6 +3,7 @@
 <script>
 window.jsTestIsAsync = true;
 description('Test that a registered Service Worker with an event handler is not garbage collected prematurely');
+var registrationObservation = null;
 var swObservation = null;
 var scope = 'gc';
 
@@ -27,7 +28,14 @@ function unregisterAndRegister(url, scope) {
     });
 }
 
-function onRegister(sw) {
+function onRegister(registration) {
+    registrationObservation = internals.observeGC(registration);
+    registration.addEventListener('updatefound', (function() {
+        onUpdate(registration.installing);
+    }));
+}
+
+function onUpdate(sw) {
     swObservation = internals.observeGC(sw);
     sw.addEventListener('statechange', onStateChange);
 }
@@ -48,6 +56,7 @@ function unregister() {
     // The worker has an event handler that can still receive the state change
     // to 'redundant', so it shouldn't be collected yet.
     gc();
+    shouldBeFalse('registrationObservation.wasCollected');
     shouldBeFalse('swObservation.wasCollected');
     navigator.serviceWorker.unregister(scope).catch(function(error) {
         testFailed('Could not unregister worker: ' + error);
@@ -58,7 +67,8 @@ function unregister() {
 function finish()
 {
     gc();
-    shouldBeTrue('swObservation.wasCollected');
+    shouldBeFalse('registrationObservation.wasCollected');
+    shouldBeFalse('swObservation.wasCollected');

[falken, 2014/08/14 10:16:36]

This test has gotten pretty silly :(  It really makes no sense for someone
reading it who doesn't know the history.

Actually our code resets registration properties, but does so just after
dispatching the statechange event for redundant. Unfortunately, I don't see a
good way to wait for a change to the registration properties.

I think we should have two test files. One that shows that registration is not
gc()'d ever and one that shows the service worker is gc()'d once registration
properties are reset (manually). I'll create these tests.

[nhiroki, 2014/08/14 13:22:07]

Acknowledged.

     finishJSTest();
 }
 </script>