Migrate some tests to use ServiceWorkerRegistration.unregister()

LayoutTests/http/tests/serviceworker/unregister.html

Index: LayoutTests/http/tests/serviceworker/unregister.html
diff --git a/LayoutTests/http/tests/serviceworker/unregister.html b/LayoutTests/http/tests/serviceworker/unregister.html
index 1aa8417543a7ff4ce558e81de1f925aba341e567..5917494d713d99a04acb108c678859b46e06dc0a 100644
--- a/LayoutTests/http/tests/serviceworker/unregister.html
+++ b/LayoutTests/http/tests/serviceworker/unregister.html
@@ -16,28 +16,35 @@ async_test(function(t) {
 }, 'Unregistering out of origin');
 
 async_test(function(t) {
-  navigator.serviceWorker.unregister('/nothing-here/')
+  var scope = 'scope/unregister-twice';

[nhiroki, 2014/08/15 09:53:40]

These should be 4-indents?
https://sites.google.com/a/chromium.org/dev/blink/serviceworker/testing?pli=1...

+  var registration;
+  navigator.serviceWorker.register('resources/empty-worker.js', {scope: scope})
+    .then(function(r) {
+        registration = r;
+        return registration.unregister();
+      })
+    .then(function() {
+        return registration.unregister();
+      })
     .then(function(value) {
-      assert_equals(value, undefined,
-                    'unregistering with no existing registration should ' +
-                    'succeed with no value');
-      t.done();
-    })
+        assert_equals(value, undefined,
+                      'unregistering twice should succeed with no value');
+        t.done();
+      })
     .catch(unreached_rejection(t));
-}, 'Unregistering with no existing registration');
+}, 'Unregister twice');
 
 async_test(function(t) {
-  var scope = '/register-then-unregister/';
-  navigator.serviceWorker.register(
-    'resources/empty-worker.js', {scope: scope})
-    .then(function(worker) {
-      return navigator.serviceWorker.unregister(scope);
-    })
+  var scope = 'scope/successful-unregister/';
+  navigator.serviceWorker.register('resources/empty-worker.js', {scope: scope})
+    .then(function(registration) {
+        return registration.unregister();
+      })
     .then(function(value) {
-      assert_equals(value, undefined,
-                    'successful unregistration should succeed with no value');
-      t.done();
-    })
+        assert_equals(value, undefined,
+                      'successful unregistration should succeed with no value');
+        t.done();
+      })
     .catch(unreached_rejection(t));
 }, 'Register then unregister');
 
@@ -64,5 +71,4 @@ async_test(function(t) {
     })
     .catch(unreached_rejection(t));
 }, 'Unregistering with default scope');
-
 </script>