[es6] Reintroduce the instanceof operator in the backends.

src/lookup.cc

Index: src/lookup.cc
diff --git a/src/lookup.cc b/src/lookup.cc
index c22c44ffcc3d9418933c4edb5239e003772fc623..bdb9f0a48e9130e09983937767a4c67dbe7b1b8d 100644
--- a/src/lookup.cc
+++ b/src/lookup.cc
@@ -191,6 +191,9 @@ void LookupIterator::InternalUpdateProtector() {
   } else if (*name_ == heap()->is_concat_spreadable_symbol()) {
     if (!isolate_->IsIsConcatSpreadableLookupChainIntact()) return;
     isolate_->InvalidateIsConcatSpreadableProtector();
+  } else if (*name_ == heap()->has_instance_symbol()) {
+    if (!isolate_->IsHasInstanceLookupChainIntact()) return;
+    isolate_->InvalidateHasInstanceProtector();
   }
 }