ServiceWorker: Add support for .skipWaiting and controllerchange event(2/3)

content/browser/service_worker/service_worker_provider_host.cc

Index: content/browser/service_worker/service_worker_provider_host.cc
diff --git a/content/browser/service_worker/service_worker_provider_host.cc b/content/browser/service_worker/service_worker_provider_host.cc
index e16454558e0ec9cc46862b3110a811dcf3bfca6f..080d05e49324c152d88af644dfb5017b8008d5b9 100644
--- a/content/browser/service_worker/service_worker_provider_host.cc
+++ b/content/browser/service_worker/service_worker_provider_host.cc
@@ -55,6 +55,21 @@ void ServiceWorkerProviderHost::OnRegistrationFailed(
   DisassociateRegistration();
 }
 
+void ServiceWorkerProviderHost::OnVersionAttributesChanged(
+    ServiceWorkerRegistration* registration,
+    ChangedVersionAttributesMask changed_mask,
+    const ServiceWorkerRegistrationInfo& info) {
+  DCHECK_EQ(associated_registration_.get(), registration);
+  scoped_refptr<ServiceWorkerVersion> active_version =
+      registration->active_version();
+  if (active_version.get() && active_version->skip_waiting() &&
+      active_version->status() == ServiceWorkerVersion::INSTALLED) {
+    active_version->RegisterStatusChangeCallback(
+        base::Bind(&ServiceWorkerProviderHost::SetControllerVersionAttribute,
+                   AsWeakPtr(), active_version));
+  }
+}
+
 void ServiceWorkerProviderHost::SetDocumentUrl(const GURL& url) {
   DCHECK(!url.has_ref());
   document_url_ = url;