Oilpan: Remove most WillBe types from the code base

third_party/WebKit/Source/core/dom/LiveNodeListBase.h

Index: third_party/WebKit/Source/core/dom/LiveNodeListBase.h
diff --git a/third_party/WebKit/Source/core/dom/LiveNodeListBase.h b/third_party/WebKit/Source/core/dom/LiveNodeListBase.h
index 306d3e8a1df0efa7f7cf9154f222895f438a90d3..f4657550095984e13c7b4a69136844ea41987344 100644
--- a/third_party/WebKit/Source/core/dom/LiveNodeListBase.h
+++ b/third_party/WebKit/Source/core/dom/LiveNodeListBase.h
@@ -39,7 +39,7 @@ enum class NodeListRootType {
     TreeScope,
 };
 
-class CORE_EXPORT LiveNodeListBase : public WillBeGarbageCollectedMixin {
+class CORE_EXPORT LiveNodeListBase : public GarbageCollectedMixin {
 public:
     LiveNodeListBase(ContainerNode& ownerNode, NodeListRootType rootType, NodeListInvalidationType invalidationType,
         CollectionType collectionType)
@@ -88,7 +88,7 @@ protected:
     DEFINE_INLINE_VIRTUAL_TRACE() { visitor->trace(m_ownerNode); }
 
 private:
-    RefPtrWillBeMember<ContainerNode> m_ownerNode; // Cannot be null.
+    Member<ContainerNode> m_ownerNode; // Cannot be null.
     const unsigned m_rootType : 1;
     const unsigned m_invalidationType : 4;
     const unsigned m_collectionType : 5;