EventSender<T> singletons are better off on the Oilpan heap.

third_party/WebKit/Source/core/svg/SVGStyleElement.h

 /*
  * Copyright (C) 2004, 2005 Nikolas Zimmermann <zimmermann@kde.org>
  * Copyright (C) 2004, 2005, 2006, 2007 Rob Buis <buis@kde.org>
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
  * License as published by the Free Software Foundation; either
  * version 2 of the License, or (at your option) any later version.
  *
  * This library is distributed in the hope that it will be useful,
@@ skipping 11 matching lines @@
 #define SVGStyleElement_h
 
 #include "core/SVGNames.h"
 #include "core/dom/StyleElement.h"
 #include "core/events/EventSender.h"
 #include "core/svg/SVGElement.h"
 #include "platform/heap/Handle.h"
 
 namespace blink {
 
-typedef EventSender<SVGStyleElement> SVGStyleEventSender;
+using SVGStyleEventSender = EventSender<SVGStyleElement>;
 
 class SVGStyleElement final : public SVGElement
                             , public StyleElement {
     DEFINE_WRAPPERTYPEINFO();
     WILL_BE_USING_GARBAGE_COLLECTED_MIXIN(SVGStyleElement);
 public:
     static PassRefPtrWillBeRawPtr<SVGStyleElement> create(Document&, bool createdByParser);
     ~SVGStyleElement() override;
 
     using StyleElement::sheet;
@@ skipping 27 matching lines @@
     bool layoutObjectIsNeeded(const ComputedStyle&) override { return false; }
 
     bool sheetLoaded() override { return StyleElement::sheetLoaded(document()); }
     void notifyLoadedSheetAndAllCriticalSubresources(LoadedSheetErrorStatus) override;
     void startLoadingDynamicSheet() override { StyleElement::startLoadingDynamicSheet(document()); }
 };
 
 } // namespace blink
 
 #endif // SVGStyleElement_h