Oilpan: move DOM string collection objects to the Oilpan heap.

Source/core/html/HTMLLinkElement.cpp

Index: Source/core/html/HTMLLinkElement.cpp
diff --git a/Source/core/html/HTMLLinkElement.cpp b/Source/core/html/HTMLLinkElement.cpp
index f85d7e86fe6e8e5c8f8a36ba1cdd5b3cd2b192f6..247fac00abd5e3fc9571b534943417094bae0ab4 100644
--- a/Source/core/html/HTMLLinkElement.cpp
+++ b/Source/core/html/HTMLLinkElement.cpp
@@ -419,6 +419,12 @@ DOMSettableTokenList* HTMLLinkElement::sizes() const
     return m_sizes.get();
 }
 
+void HTMLLinkElement::trace(Visitor* visitor)
+{
+    visitor->trace(m_sizes);
+    HTMLElement::trace(visitor);
+}
+
 PassOwnPtr<LinkStyle> LinkStyle::create(HTMLLinkElement* owner)
 {
     return adoptPtr(new LinkStyle(owner));