ServiceWorker: Get registration info and its version attributes in one lock operation

content/child/service_worker/web_service_worker_provider_impl.cc

Index: content/child/service_worker/web_service_worker_provider_impl.cc
diff --git a/content/child/service_worker/web_service_worker_provider_impl.cc b/content/child/service_worker/web_service_worker_provider_impl.cc
index 851fad940c40bb33d054787505206cf363bc66f7..11b44b5cf089a8230334226db651dd6c386abeb4 100644
--- a/content/child/service_worker/web_service_worker_provider_impl.cc
+++ b/content/child/service_worker/web_service_worker_provider_impl.cc
@@ -49,20 +49,20 @@ void WebServiceWorkerProviderImpl::setClient(
   // for more context)
   GetDispatcher()->AddProviderClient(provider_id_, client);
 
-  if (!context_->registration()) {
-    // This provider is not associated with any registration.
+  if (!context_->IsAssociatedWithRegistration())

[Kunihiko Sakamoto, 2015/01/28 06:38:55]

I wonder if this and GetRegistrationInfoAndVersionAttributes() below should be
atomic as well?

[nhiroki, 2015/01/28 07:42:27]

Good point. Done.

     return;
-  }
 
   // Set .ready if the associated registration has the active service worker.
   if (context_->active_handle_id() != kInvalidServiceWorkerHandleId) {
+    ServiceWorkerRegistrationObjectInfo info;
+    ServiceWorkerVersionAttributes attrs;
+    context_->GetRegistrationInfoAndVersionAttributes(&info, &attrs);
+
     WebServiceWorkerRegistrationImpl* registration =
-        GetDispatcher()->FindServiceWorkerRegistration(
-            context_->registration()->info(), false);
+        GetDispatcher()->FindServiceWorkerRegistration(info, false);
     if (!registration) {
-      registration = GetDispatcher()->CreateServiceWorkerRegistration(
-          context_->registration()->info(), false);
-      ServiceWorkerVersionAttributes attrs = context_->GetVersionAttributes();
+      registration =
+          GetDispatcher()->CreateServiceWorkerRegistration(info, false);
       registration->SetInstalling(
           GetDispatcher()->GetServiceWorker(attrs.installing, false));
       registration->SetWaiting(