Rewind additional parser state when reinterpreting arrow arguments

src/parser.h

Index: src/parser.h
diff --git a/src/parser.h b/src/parser.h
index fd24e8d4e952b4d33408f3fc03c0fcb83ec3bf43..e3cee84097346b881e8b1e9f744af1cb4a150a02 100644
--- a/src/parser.h
+++ b/src/parser.h
@@ -355,6 +355,21 @@ class ParserTraits {
     typedef Variable GeneratorVariable;
     typedef v8::internal::Zone Zone;
 
+    class Checkpoint BASE_EMBEDDED {
+     public:
+      template <typename Parser>
+      explicit Checkpoint(Parser* parser) {
+        isolate_ = parser->zone()->isolate();
+        saved_ast_node_id_ = isolate_->ast_node_id();
+      }
+
+      void Restore() { isolate_->set_ast_node_id(saved_ast_node_id_); }
+
+     private:
+      Isolate* isolate_;
+      int saved_ast_node_id_;
+    };
+
     typedef v8::internal::AstProperties AstProperties;
     typedef Vector<VariableProxy*> ParameterIdentifierVector;