Improve DEFINE_STATIC_LOCAL()'s handling of Blink GCed objects.

third_party/WebKit/Source/core/html/HTMLMediaElement.cpp

 /*
  * Copyright (C) 2007, 2008, 2009, 2010, 2011, 2012, 2013 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 122 matching lines @@
 }
 
 const char* boolString(bool val)
 {
     return val ? "true" : "false";
 }
 #endif
 
 DocumentElementSetMap& documentToElementSetMap()
 {
-    DEFINE_STATIC_LOCAL(Persistent<DocumentElementSetMap>, map, (new DocumentElementSetMap()));
-    return *map;
+    DEFINE_STATIC_LOCAL(DocumentElementSetMap, map, (new DocumentElementSetMap));
+    return map;
 }
 
 void addElementToDocumentMap(HTMLMediaElement* element, Document* document)
 {
     DocumentElementSetMap& map = documentToElementSetMap();
     WeakMediaElementSet set = map.take(document);
     set.add(element);
     map.add(document, set);
 }
 
@@ skipping 3715 matching lines @@
 }
 
 #if !ENABLE(OILPAN)
 WeakPtr<HTMLMediaElement> HTMLMediaElement::createWeakPtr()
 {
     return m_weakPtrFactory.createWeakPtr();
 }
 #endif
 
 } // namespace blink