Add Event::create() that takes EventInitDictionary

Source/core/events/Event.h

Index: Source/core/events/Event.h
diff --git a/Source/core/events/Event.h b/Source/core/events/Event.h
index ad5558b30ae1346e3cfdb37c5e26b3c616b4ce52..3a0a66575a36dcf4d0b25d4f885d5f38900a1149 100644
--- a/Source/core/events/Event.h
+++ b/Source/core/events/Event.h
@@ -107,10 +107,15 @@ public:
         return adoptRefWillBeNoop(new Event(type, true, true));
     }
 
+    // TODO(bashi): Remove this when we remove all [EventConstructor].
     static PassRefPtrWillBeRawPtr<Event> create(const AtomicString& type, const EventInit& initializer)
     {
         return adoptRefWillBeNoop(new Event(type, initializer));
     }
+    static PassRefPtrWillBeRawPtr<Event> create(const AtomicString& type, const EventInitDictionary& initializer)
+    {
+        return adoptRefWillBeNoop(new Event(type, initializer));
+    }
 
     virtual ~Event();