Oilpan: Remove guardRef and guardDeref from TreeScope.

Source/core/dom/Element.cpp

Index: Source/core/dom/Element.cpp
diff --git a/Source/core/dom/Element.cpp b/Source/core/dom/Element.cpp
index 441889f2a9333fa4d77f086554b8cf52d10facf1..fa1fe9d69dc015eedbf60c6869b81d26988356bb 100644
--- a/Source/core/dom/Element.cpp
+++ b/Source/core/dom/Element.cpp
@@ -178,10 +178,17 @@ Element::~Element()
     if (hasSyntheticAttrChildNodes())
         detachAllAttrNodesFromElement();
 
+#if !ENABLE(OILPAN)
+    // With Oilpan, either the Element has been removed from the Document
+    // or the Document is dead as well. If the Element has been removed from
+    // the Document the element has already been removed from the pending
+    // resources. If the document is also dead, there is no need to remove
+    // the element from the pending resources.
     if (hasPendingResources()) {
         document().accessSVGExtensions().removeElementFromPendingResources(this);
         ASSERT(!hasPendingResources());
     }
+#endif
 }
 
 inline ElementRareData* Element::elementRareData() const