Oilpan: Remove Element* raw pointers in objects

Source/core/css/CSSFontFaceSrcValue.cpp

 /*
  * Copyright (C) 2007, 2010 Apple Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 123 matching lines @@
 
     FetchRequest request(ResourceRequest(resourceURL), FetchInitiatorTypeNames::css);
     document->fetcher()->requestLoadStarted(m_fetched.get(), request, ResourceFetcher::ResourceLoadingFromCache);
 }
 
 bool CSSFontFaceSrcValue::equals(const CSSFontFaceSrcValue& other) const
 {
     return m_isLocal == other.m_isLocal && m_format == other.m_format && m_resource == other.m_resource;
 }
 
+void CSSFontFaceSrcValue::traceAfterDispatch(Visitor* visitor)
+{
+    visitor->trace(m_svgFontFaceElement);
+    CSSValue::traceAfterDispatch(visitor);
 }
+
+}