[Background Sync] Converting Blink code to the MVP API

Source/modules/background_sync/PeriodicSyncEvent.h

Index: Source/modules/background_sync/PeriodicSyncEvent.h
diff --git a/Source/modules/background_sync/PeriodicSyncEvent.h b/Source/modules/background_sync/PeriodicSyncEvent.h
new file mode 100644
index 0000000000000000000000000000000000000000..94d30c20a2b6eee6b4c2fe30978520cc850a10cf
--- /dev/null
+++ b/Source/modules/background_sync/PeriodicSyncEvent.h
@@ -0,0 +1,51 @@
+// 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.
+
+#ifndef PeriodicSyncEvent_h
+#define PeriodicSyncEvent_h
+
+#include "modules/EventModules.h"
+#include "modules/serviceworkers/ExtendableEvent.h"
+#include "wtf/text/AtomicString.h"
+
+namespace blink {
+
+class PeriodicSyncEventInit;
+class PeriodicSyncRegistration;
+
+class PeriodicSyncEvent final : public ExtendableEvent {
+    DEFINE_WRAPPERTYPEINFO();
+public:
+    static PassRefPtrWillBeRawPtr<PeriodicSyncEvent> create()
+    {
+        return adoptRefWillBeNoop(new PeriodicSyncEvent);
+    }
+    static PassRefPtrWillBeRawPtr<PeriodicSyncEvent> create(const AtomicString& type, PeriodicSyncRegistration* syncRegistration, WaitUntilObserver* observer)
+    {
+        return adoptRefWillBeNoop(new PeriodicSyncEvent(type, syncRegistration, observer));
+    }
+    static PassRefPtrWillBeRawPtr<PeriodicSyncEvent> create(const AtomicString& type, const PeriodicSyncEventInit& init)
+    {
+        return adoptRefWillBeNoop(new PeriodicSyncEvent(type, init));
+    }
+
+    virtual ~PeriodicSyncEvent();
+
+    virtual const AtomicString& interfaceName() const override;
+
+    PeriodicSyncRegistration* registration();
+
+    DECLARE_VIRTUAL_TRACE();
+
+private:
+    PeriodicSyncEvent();
+    PeriodicSyncEvent(const AtomicString& type, PeriodicSyncRegistration*, WaitUntilObserver*);
+    PeriodicSyncEvent(const AtomicString& type, const PeriodicSyncEventInit&);
+
+    PersistentWillBeMember<PeriodicSyncRegistration> m_periodicRegistration;
+};
+
+} // namespace blink
+
+#endif // PeriodicSyncEvent_h