[Oilpan]: Make StylePropertySet fully garbage collected.

Source/core/dom/ElementDataCache.h

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 #ifndef ElementDataCache_h
 #define ElementDataCache_h
 
+#include "platform/heap/Handle.h"
 #include "wtf/HashMap.h"
 #include "wtf/PassOwnPtr.h"
 #include "wtf/PassRefPtr.h"
 #include "wtf/RefPtr.h"
 #include "wtf/Vector.h"
 #include "wtf/text/StringHash.h"
 
 namespace WebCore {
 
 class Attribute;
 class ShareableElementData;
 class ShareableElementDataCacheEntry;
 
 class ElementDataCache {

[haraken, 2014/05/08 11:43:45]

You might want to move this to the heap in a follow-up.

[wibling-chromium, 2014/05/08 12:38:55]

Yes, that is a prime candidate for a subsequent change.

 public:
     static PassOwnPtr<ElementDataCache> create() { return adoptPtr(new ElementDataCache); }
     ~ElementDataCache();
 
-    PassRefPtr<ShareableElementData> cachedShareableElementDataWithAttributes(const Vector<Attribute>&);
+    PassRefPtrWillBeRawPtr<ShareableElementData> cachedShareableElementDataWithAttributes(const Vector<Attribute>&);
 
 private:
     ElementDataCache();
 
-    typedef HashMap<unsigned, RefPtr<ShareableElementData>, AlreadyHashed> ShareableElementDataCache;
+    typedef WillBePersistentHeapHashMap<unsigned, RefPtrWillBeMember<ShareableElementData>, AlreadyHashed> ShareableElementDataCache;
     ShareableElementDataCache m_shareableElementDataCache;
 };
 
 }
 
 #endif