Convert raw pointer to PassOwnPtr for EventFactoryBase

Source/core/events/EventFactory.h

Index: Source/core/events/EventFactory.h
diff --git a/Source/core/events/EventFactory.h b/Source/core/events/EventFactory.h
index 78f7be1869a60a7998f61bf87d599d185b67f46d..df9cde337a7977c13b0de89ac6550bb53cb58b99 100644
--- a/Source/core/events/EventFactory.h
+++ b/Source/core/events/EventFactory.h
@@ -37,10 +37,19 @@ class Event;
 class EventFactoryBase {
 public:
     virtual PassRefPtrWillBeRawPtr<Event> create(const String& eventType) = 0;
+    virtual ~EventFactoryBase() { }
+
+protected:
+    EventFactoryBase() { }
 };
 
-class EventFactory : public EventFactoryBase {
+class EventFactory FINAL : public EventFactoryBase {
 public:
+    static PassOwnPtr<EventFactory> create()
+    {
+        return adoptPtr(new EventFactory());
+    }
+
     virtual PassRefPtrWillBeRawPtr<Event> create(const String& eventType) OVERRIDE;
 };