Start adding support for elements to the LookupIterator

src/lookup-inl.h

Index: src/lookup-inl.h
diff --git a/src/lookup-inl.h b/src/lookup-inl.h
index a801e3493e54124c2bc211daa7c2afe0f4b2747f..f48096fb3827dabf1d354e1c1db7dcedb1959fd3 100644
--- a/src/lookup-inl.h
+++ b/src/lookup-inl.h
@@ -42,22 +42,29 @@ LookupIterator::State LookupIterator::LookupInHolder(Map* const map,
     case NOT_FOUND:
       if (map->IsJSProxyMap()) return JSPROXY;
       if (map->is_access_check_needed() &&
-          !isolate_->IsInternallyUsedPropertyName(name_)) {
+          (IsElement() || !isolate_->IsInternallyUsedPropertyName(name_))) {
         return ACCESS_CHECK;
       }
     // Fall through.
     case ACCESS_CHECK:
-      if (exotic_index_state_ != ExoticIndexState::kNoIndex &&
+      if (exotic_index_state_ != ExoticIndexState::kNotExotic &&
           IsIntegerIndexedExotic(holder)) {
         return INTEGER_INDEXED_EXOTIC;
       }
-      if (check_interceptor() && map->has_named_interceptor() &&
+      if (check_interceptor() && HasInterceptor(map) &&
           !SkipInterceptor(JSObject::cast(holder))) {
         return INTERCEPTOR;
       }
     // Fall through.
     case INTERCEPTOR:
-      if (map->is_dictionary_map()) {
+      if (IsElement()) {
+        JSObject* js_object = JSObject::cast(holder);
+        ElementsAccessor* accessor = js_object->GetElementsAccessor();
+        FixedArrayBase* backing_store = js_object->elements();
+        number_ = accessor->GetIndexForKey(backing_store, index_);
+        if (number_ == kMaxUInt32) return NOT_FOUND;
+        property_details_ = accessor->GetDetails(backing_store, number_);
+      } else if (map->is_dictionary_map()) {
         NameDictionary* dict = JSObject::cast(holder)->property_dictionary();
         number_ = dict->FindEntry(name_);
         if (number_ == NameDictionary::kNotFound) return NOT_FOUND;
@@ -97,7 +104,7 @@ LookupIterator::State LookupIterator::LookupNonMaskingInterceptorInHolder(
     Map* const map, JSReceiver* const holder) {
   switch (state_) {
     case NOT_FOUND:
-      if (check_interceptor() && map->has_named_interceptor() &&
+      if (check_interceptor() && HasInterceptor(map) &&
           !SkipInterceptor(JSObject::cast(holder))) {
         return INTERCEPTOR;
       }