ServiceWorker: Change the return value of ServiceWorkerRegistration::unregister to boolean (3/4)

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 ae3bcae6ea185f0c1e36c7225a8d0a9e8e5bec45..c629ca0e7c88778c2957e92bbba24609134a7f7a 100644
--- a/LayoutTests/http/tests/serviceworker/unregister.html
+++ b/LayoutTests/http/tests/serviceworker/unregister.html
@@ -28,8 +28,11 @@ async_test(function(t) {
           return registration.unregister();
         })
       .then(function(value) {
-          assert_equals(value, undefined,
-                        'unregistering twice should resolve with no value');
+          // FIXME: This value must be false in spec,
+          // but this is not supported now.
+          // See: https://crbug.com/390894#c16
+          assert_equals(value, true,
+                        'unregistering twice should resolve with true');
           t.done();
         })
       .catch(unreached_rejection(t));
@@ -43,8 +46,8 @@ async_test(function(t) {
           return registration.unregister();
         })
       .then(function(value) {
-          assert_equals(value, undefined,
-                        'unregistration should resolve with no value');
+          assert_equals(value, true,
+                        'unregistration should resolve with true');
           t.done();
         })
       .catch(unreached_rejection(t));
@@ -65,7 +68,7 @@ async_test(function(t) {
           return navigator.serviceWorker.unregister();
         })
       .then(function(value) {
-          assert_equals(value, undefined,
+          assert_equals(value, true,
                         'unregister with default scope should succeed');
           return state_promise;
         })