Oilpan: "Move" ElementStyleResources to the oilpan heap.

Source/core/css/resolver/CSSToStyleMap.h

Index: Source/core/css/resolver/CSSToStyleMap.h
diff --git a/Source/core/css/resolver/CSSToStyleMap.h b/Source/core/css/resolver/CSSToStyleMap.h
index b84b0250bf1f2293a6e54fa504a6dda953eba39b..2e5188338485c4961feb14e6f27b31c75cefe1d5 100644
--- a/Source/core/css/resolver/CSSToStyleMap.h
+++ b/Source/core/css/resolver/CSSToStyleMap.h
@@ -44,10 +44,10 @@ class BorderImageLengthBox;
 // CSSValue objects into their RenderStyle equivalents.
 
 class CSSToStyleMap {
+    STACK_ALLOCATED();
     WTF_MAKE_NONCOPYABLE(CSSToStyleMap);
 public:
     CSSToStyleMap(const StyleResolverState& state, ElementStyleResources& elementStyleResources) : m_state(state), m_elementStyleResources(elementStyleResources) { }
-
     void mapFillAttachment(CSSPropertyID, FillLayer*, CSSValue*) const;
     void mapFillClip(CSSPropertyID, FillLayer*, CSSValue*) const;
     void mapFillComposite(CSSPropertyID, FillLayer*, CSSValue*) const;