[Heap] Remove concept of MarkingParity.

src/builtins/builtins.h

Index: src/builtins/builtins.h
diff --git a/src/builtins/builtins.h b/src/builtins/builtins.h
index 6c0b72a913b65a89b568dec0b884572afc936e80..05a5431f2d99b73ee2339608384e5429ca7e4476 100644
--- a/src/builtins/builtins.h
+++ b/src/builtins/builtins.h
@@ -29,9 +29,7 @@ namespace internal {
   V(NoAge)                        \
   CODE_AGE_LIST_WITH_ARG(CODE_AGE_LIST_IGNORE_ARG, V)
 
-#define DECLARE_CODE_AGE_BUILTIN(C, V) \
-  V(Make##C##CodeYoungAgainOddMarking) \
-  V(Make##C##CodeYoungAgainEvenMarking)
+#define DECLARE_CODE_AGE_BUILTIN(C, V) V(Make##C##CodeYoungAgain)
 
 // CPP: Builtin in C++. Entered via BUILTIN_EXIT frame.
 //      Args: name