Change various helper classes to transition types to get CSSValue entirely onto the gc heap.

Source/core/css/resolver/MediaQueryResult.h

Index: Source/core/css/resolver/MediaQueryResult.h
diff --git a/Source/core/css/resolver/MediaQueryResult.h b/Source/core/css/resolver/MediaQueryResult.h
index 1dc00f42dc31c621d290407328d06229fc0e58ff..a809bf9be41fb0cd40085e6214331f9077aaaab7 100644
--- a/Source/core/css/resolver/MediaQueryResult.h
+++ b/Source/core/css/resolver/MediaQueryResult.h
@@ -29,8 +29,8 @@
 
 namespace WebCore {
 
-class MediaQueryResult : public RefCounted<MediaQueryResult> {
-    WTF_MAKE_NONCOPYABLE(MediaQueryResult); WTF_MAKE_FAST_ALLOCATED;
+class MediaQueryResult : public RefCountedWillBeGarbageCollectedFinalized<MediaQueryResult> {
+    WTF_MAKE_NONCOPYABLE(MediaQueryResult); WTF_MAKE_FAST_ALLOCATED_WILL_BE_REMOVED;
 public:
     MediaQueryResult(const MediaQueryExp& expr, bool result)
         : m_expression(expr)
@@ -38,6 +38,8 @@ public:
     {
     }
 
+    void trace(Visitor* visitor) { visitor->trace(m_expression); }
+
     MediaQueryExp m_expression;
     bool m_result;
 };