update vector ics to handle megamorphic keyed loads

src/type-feedback-vector-inl.h

Index: src/type-feedback-vector-inl.h
diff --git a/src/type-feedback-vector-inl.h b/src/type-feedback-vector-inl.h
index 612004ebee7e7dc9d4b7419f6563b92325e93da4..9b64082d35cec2f314bf5f255378bd65f996a565 100644
--- a/src/type-feedback-vector-inl.h
+++ b/src/type-feedback-vector-inl.h
@@ -30,11 +30,6 @@ Handle<Object> TypeFeedbackVector::PremonomorphicSentinel(Isolate* isolate) {
 }
 
 
-Handle<Object> TypeFeedbackVector::GenericSentinel(Isolate* isolate) {
-  return isolate->factory()->generic_symbol();
-}
-
-
 Handle<Object> TypeFeedbackVector::MonomorphicArraySentinel(
     Isolate* isolate, ElementsKind elements_kind) {
   return Handle<Object>(Smi::FromInt(static_cast<int>(elements_kind)), isolate);