[Background Sync] Converting Blink code to the MVP API

Source/modules/background_sync/PeriodicSyncEvent.cpp

Index: Source/modules/background_sync/PeriodicSyncEvent.cpp
diff --git a/Source/modules/background_sync/PeriodicSyncEvent.cpp b/Source/modules/background_sync/PeriodicSyncEvent.cpp
new file mode 100644
index 0000000000000000000000000000000000000000..dc3587e4d47dcc715a01710c0b38db2e2717eff7
--- /dev/null
+++ b/Source/modules/background_sync/PeriodicSyncEvent.cpp
@@ -0,0 +1,49 @@
+// Copyright 2015 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "config.h"
+#include "modules/background_sync/PeriodicSyncEvent.h"
+
+#include "modules/background_sync/PeriodicSyncEventInit.h"
+#include "modules/background_sync/PeriodicSyncRegistration.h"
+
+namespace blink {
+
+PeriodicSyncEvent::PeriodicSyncEvent()
+{
+}
+
+PeriodicSyncEvent::PeriodicSyncEvent(const AtomicString& type, PeriodicSyncRegistration* periodicRegistration, WaitUntilObserver* observer)
+    : ExtendableEvent(type, ExtendableEventInit(), observer)
+    , m_periodicRegistration(periodicRegistration)
+{
+}
+
+PeriodicSyncEvent::PeriodicSyncEvent(const AtomicString& type, const PeriodicSyncEventInit& init)
+    : ExtendableEvent(type, init)
+{
+    m_periodicRegistration = init.registration();
+}
+
+PeriodicSyncEvent::~PeriodicSyncEvent()
+{
+}
+
+const AtomicString& PeriodicSyncEvent::interfaceName() const
+{
+    return EventNames::PeriodicSyncEvent;
+}
+
+PeriodicSyncRegistration* PeriodicSyncEvent::registration()
+{
+    return m_periodicRegistration.get();
+}
+
+DEFINE_TRACE(PeriodicSyncEvent)
+{
+    visitor->trace(m_periodicRegistration);
+    ExtendableEvent::trace(visitor);
+}
+
+} // namespace blink