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

Source/core/css/MediaQueryEvaluator.cpp

 /*
  * CSS Media Query Evaluator
  *
  * Copyright (C) 2006 Kimmo Kinnunen <kimmo.t.kinnunen@nokia.com>.
  * Copyright (C) 2013 Apple Inc. All rights reserved.
  * Copyright (C) 2013 Intel Corporation. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
@@ skipping 105 matching lines @@
 static bool applyRestrictor(MediaQuery::Restrictor r, bool value)
 {
     return r == MediaQuery::Not ? !value : value;
 }
 
 bool MediaQueryEvaluator::eval(const MediaQuerySet* querySet, MediaQueryResultList* viewportDependentMediaQueryResults) const
 {
     if (!querySet)
         return true;
 
-    const Vector<OwnPtr<MediaQuery> >& queries = querySet->queryVector();
+    const WillBeHeapVector<OwnPtrWillBeMember<MediaQuery> >& queries = querySet->queryVector();
     if (!queries.size())
         return true; // Empty query list evaluates to true.
 
     // Iterate over queries, stop if any of them eval to true (OR semantics).
     bool result = false;
     for (size_t i = 0; i < queries.size() && !result; ++i) {
         MediaQuery* query = queries[i].get();
 
         if (mediaTypeMatch(query->mediaType())) {
             const ExpressionVector& expressions = query->expressions();
@@ skipping 553 matching lines @@
     // Call the media feature evaluation function. Assume no prefix and let
     // trampoline functions override the prefix if prefix is used.
     EvalFunc func = gFunctionMap->get(expr->mediaFeature().impl());
     if (func)
         return func(expr->value(), m_style.get(), m_frame, NoPrefix);
 
     return false;
 }
 
 } // namespace