Oilpan: Reapply: Remove all the RefPtrs and most of the raw pointers to style

Source/core/css/StyleSheet.h

Index: Source/core/css/StyleSheet.h
diff --git a/Source/core/css/StyleSheet.h b/Source/core/css/StyleSheet.h
index e92a7d657aa30d54dce4dd1794b1e02b98abdbbf..8229de201ab63bcbd717ae397207624f1523872d 100644
--- a/Source/core/css/StyleSheet.h
+++ b/Source/core/css/StyleSheet.h
@@ -34,7 +34,7 @@ class MediaList;
 class Node;
 class StyleSheet;
 
-class StyleSheet : public RefCountedWillBeRefCountedGarbageCollected<StyleSheet> {
+class StyleSheet : public RefCountedWillBeGarbageCollectedFinalized<StyleSheet> {
 public:
     virtual ~StyleSheet();