Remove more bits of the Oilpan tracing system

sky/engine/wtf/VectorTraits.h

Index: sky/engine/wtf/VectorTraits.h
diff --git a/sky/engine/wtf/VectorTraits.h b/sky/engine/wtf/VectorTraits.h
index 2b6544ce35239b8d755ebc3a534c09f5d994d73e..eb41f68a3d22cc3ebfdb640f3e50236e14b2e060 100644
--- a/sky/engine/wtf/VectorTraits.h
+++ b/sky/engine/wtf/VectorTraits.h
@@ -41,10 +41,6 @@ namespace WTF {
         static const bool canCopyWithMemcpy = IsPod<T>::value;
         static const bool canFillWithMemset = IsPod<T>::value && (sizeof(T) == sizeof(char));
         static const bool canCompareWithMemcmp = IsPod<T>::value;
-        template<typename U = void>
-        struct NeedsTracingLazily {
-            static const bool value = NeedsTracing<T>::value;
-        };
         static const WeakHandlingFlag weakHandlingFlag = NoWeakHandlingInCollections; // We don't support weak handling in vectors.
     };
 
@@ -83,10 +79,6 @@ namespace WTF {
         static const bool canCopyWithMemcpy = FirstTraits::canCopyWithMemcpy && SecondTraits::canCopyWithMemcpy;
         static const bool canFillWithMemset = false;
         static const bool canCompareWithMemcmp = FirstTraits::canCompareWithMemcmp && SecondTraits::canCompareWithMemcmp;
-        template <typename U = void>
-        struct NeedsTracingLazily {
-            static const bool value = ShouldBeTraced<FirstTraits>::value || ShouldBeTraced<SecondTraits>::value;
-        };
         static const WeakHandlingFlag weakHandlingFlag = NoWeakHandlingInCollections; // We don't support weak handling in vectors.
     };