Implement kToBeExecutedOnceCodeAge.

src/objects.h

Index: src/objects.h
diff --git a/src/objects.h b/src/objects.h
index bfec7726786dabf54fdf89f122988b02df40f7f3..0234d6deb81d8140520a663fd356961b5ea136f4 100644
--- a/src/objects.h
+++ b/src/objects.h
@@ -5536,14 +5536,15 @@ class Code: public HeapObject {
 
 #define DECLARE_CODE_AGE_ENUM(X) k##X##CodeAge,
   enum Age {
+    kToBeExecutedOnceCodeAge = -3,
     kNotExecutedCodeAge = -2,
     kExecutedOnceCodeAge = -1,
     kNoAgeCodeAge = 0,
     CODE_AGE_LIST(DECLARE_CODE_AGE_ENUM)
     kAfterLastCodeAge,
-    kFirstCodeAge = kNotExecutedCodeAge,
+    kFirstCodeAge = kToBeExecutedOnceCodeAge,
     kLastCodeAge = kAfterLastCodeAge - 1,
-    kCodeAgeCount = kAfterLastCodeAge - kNotExecutedCodeAge - 1,
+    kCodeAgeCount = kAfterLastCodeAge - kFirstCodeAge - 1,
     kIsOldCodeAge = kSexagenarianCodeAge,
     kPreAgedCodeAge = kIsOldCodeAge - 1
   };
@@ -5556,13 +5557,11 @@ class Code: public HeapObject {
   static void MakeCodeAgeSequenceYoung(byte* sequence, Isolate* isolate);
   static void MarkCodeAsExecuted(byte* sequence, Isolate* isolate);
   void MakeYoung(Isolate* isolate);
+  void MarkToBeExecutedOnce(Isolate* isolate);
   void MakeOlder(MarkingParity);
   static bool IsYoungSequence(Isolate* isolate, byte* sequence);
   bool IsOld();
   Age GetAge();
-  // Gets the raw code age, including psuedo code-age values such as
-  // kNotExecutedCodeAge and kExecutedOnceCodeAge.
-  Age GetRawAge();
   static inline Code* GetPreAgedCodeAgeStub(Isolate* isolate) {
     return GetCodeAgeStub(isolate, kNotExecutedCodeAge, NO_MARKING_PARITY);
   }