[Background Sync] Align exposed API with spec

third_party/WebKit/Source/modules/background_sync/SyncCallbacks.cpp

Index: third_party/WebKit/Source/modules/background_sync/SyncCallbacks.cpp
diff --git a/third_party/WebKit/Source/modules/background_sync/SyncCallbacks.cpp b/third_party/WebKit/Source/modules/background_sync/SyncCallbacks.cpp
index c0cd78e2147e25497f745ea0b814a96707589e34..9f31ab12f822b414ca655d4da46fc0b9efe03a60 100644
--- a/third_party/WebKit/Source/modules/background_sync/SyncCallbacks.cpp
+++ b/third_party/WebKit/Source/modules/background_sync/SyncCallbacks.cpp
@@ -120,20 +120,14 @@ SyncGetRegistrationsCallbacks::~SyncGetRegistrationsCallbacks()
 
 void SyncGetRegistrationsCallbacks::onSuccess(const WebVector<WebSyncRegistration*>& webSyncRegistrations)
 {
-    Vector<OwnPtr<WebSyncRegistration>> registrations;
-    for (WebSyncRegistration* r : webSyncRegistrations) {
-        registrations.append(adoptPtr(r));
-    }
     if (!m_resolver->executionContext() || m_resolver->executionContext()->activeDOMObjectsAreStopped()) {
         return;
     }
-
-    HeapVector<Member<SyncRegistration>> syncRegistrations;
-    for (auto& r : registrations) {
-        SyncRegistration* reg = SyncRegistration::take(m_resolver.get(), r.release(), m_serviceWorkerRegistration);
-        syncRegistrations.append(reg);
+    Vector<String> tags;
+    for (const WebSyncRegistration* r : webSyncRegistrations) {
+        tags.append(r->tag);
     }
-    m_resolver->resolve(syncRegistrations);
+    m_resolver->resolve(tags);
 }
 
 void SyncGetRegistrationsCallbacks::onError(const WebSyncError& error)