[ServiceWorker] Update formatting for tests.

LayoutTests/http/tests/serviceworker/resources/test-helpers.js

 // Adapter for testharness.js-style tests with Service Workers
 
 function service_worker_unregister_and_register(test, url, scope) {
-    var options = scope ? { scope: scope } : {};
-    return navigator.serviceWorker.unregister(scope).then(
-        test.step_func(function() {
-            return navigator.serviceWorker.register(url, options);
-        }),
-        unreached_rejection(test, 'Unregister should not fail')
-    ).then(test.step_func(function(worker) {
-          return Promise.resolve(worker);
-        }),
-        unreached_rejection(test, 'Registration should not fail')
-    );
+  var options = scope ? {scope: scope} : {};
+  return navigator.serviceWorker.unregister(scope)
+    .catch(unreached_rejection(test, 'Unregister should not fail'))
+    .then(test.step_func(function() {
+        return navigator.serviceWorker.register(url, options);
+      }))
+    .catch(unreached_rejection(test, 'Registration should not fail'));
 }
 
 function service_worker_unregister_and_done(test, scope) {
-    return navigator.serviceWorker.unregister(scope).then(
-        test.done.bind(test),
-        unreached_rejection(test, 'Unregister should not fail'));
+  return navigator.serviceWorker.unregister(scope)
+    .then(test.done.bind(test),
+          unreached_rejection(test, 'Unregister should not fail'));
 }
 
 // Rejection-specific helper that provides more details
 function unreached_rejection(test, prefix) {
-    return test.step_func(function(error) {
-        var reason = error.name ? error.name : error;
-        var prefix = prefix ? prefix : "unexpected rejection";
-        assert_unreached(prefix + ': ' + reason);
+  return test.step_func(function(error) {
+      var reason = error.message || error.name || error;

[falken, 2014/08/07 12:45:45]

Thank you for this!!! I've been using this locally and might end up checking it
in if a patch of mine lands before yours.

+      var error_prefix = prefix || 'unexpected rejection';
+      assert_unreached(error_prefix + ': ' + reason);
     });
 }
 
 // FIXME: Clean up the iframe when the test completes.
 function with_iframe(url, f) {
-    return new Promise(function(resolve, reject) {
-        var frame = document.createElement('iframe');
-        frame.src = url;
-        frame.onload = function() {
-            if (f) {
-              f(frame);
-            }
-            resolve(frame);
-        };
-        document.body.appendChild(frame);
+  return new Promise(function(resolve, reject) {
+      var frame = document.createElement('iframe');
+      frame.src = url;
+      frame.onload = function() {
+        if (f) {
+          f(frame);
+        }
+        resolve(frame);
+      };
+      document.body.appendChild(frame);
     });
 }
 
 function normalizeURL(url) {
   return new URL(url, document.location).toString().replace(/#.*$/, '');
 }
 
 function wait_for_state(test, worker, state) {
-    return new Promise(test.step_func(function(resolve, reject) {
-        worker.addEventListener('statechange', test.step_func(function() {
+  return new Promise(test.step_func(function(resolve, reject) {
+      worker.addEventListener('statechange',
+                              test.step_func(function() {
             if (worker.state === state)
-                resolve(state);
-        }));
+              resolve(state);
+          }));
     }));
 }
 
 (function() {
   function fetch_tests_from_worker(worker) {
     return new Promise(function(resolve, reject) {
         var messageChannel = new MessageChannel();
         messageChannel.port1.addEventListener('message', function(message) {
             if (message.data.type == 'complete') {
               synthesize_tests(message.data.tests, message.data.status);
@@ skipping 35 matching lines @@
     var test = async_test(description);
     service_worker_unregister_and_register(test, url, scope)
       .then(function(worker) { return fetch_tests_from_worker(worker); })
       .then(function() { return navigator.serviceWorker.unregister(scope); })
       .then(function() { test.done(); })
       .catch(test.step_func(function(e) { throw e; }));
   };
 
   self.service_worker_test = service_worker_test;
 })();