Revert "Add a premonomorphic state to the call target cache."

src/objects.h

Index: src/objects.h
diff --git a/src/objects.h b/src/objects.h
index c5cd1937e95b9ab252ee654e242d812a945a9980..3692922c090551f30b8596d0183591235c407c3c 100644
--- a/src/objects.h
+++ b/src/objects.h
@@ -8172,9 +8172,6 @@ class TypeFeedbackInfo: public Struct {
   // The object that indicates an uninitialized cache.
   static inline Handle<Object> UninitializedSentinel(Isolate* isolate);
 
-  // The object that indicates a cache in pre-monomorphic state.
-  static inline Handle<Object> PremonomorphicSentinel(Isolate* isolate);
-
   // The object that indicates a megamorphic state.
   static inline Handle<Object> MegamorphicSentinel(Isolate* isolate);