Also use transition types when constructing Events that raise exceptions.

Source/bindings/templates/interface.cpp

Index: Source/bindings/templates/interface.cpp
diff --git a/Source/bindings/templates/interface.cpp b/Source/bindings/templates/interface.cpp
index 01f4a6c16627d12e4017dbb6a3a490874ba00c3e..99901e01def9490c6d6fa20cc1f5e52b0911c500 100644
--- a/Source/bindings/templates/interface.cpp
+++ b/Source/bindings/templates/interface.cpp
@@ -643,7 +643,7 @@ static void constructor(const v8::FunctionCallbackInfo<v8::Value>& info)
         {% endfor %}
     }
     {% if is_constructor_raises_exception %}
-    RefPtr<{{cpp_class}}> event = {{cpp_class}}::create(type, eventInit, exceptionState);
+    RefPtrWillBeRawPtr<{{cpp_class}}> event = {{cpp_class}}::create(type, eventInit, exceptionState);
     if (exceptionState.throwIfNeeded())
         return;
     {% else %}