Set up rewriting triggers

src/parsing/preparser.h

Index: src/parsing/preparser.h
diff --git a/src/parsing/preparser.h b/src/parsing/preparser.h
index 9253ad5e518f93b9cfc08393a475912eb6377e85..7bc0a2530a6eb2e886a2b4f7810092b12a443053 100644
--- a/src/parsing/preparser.h
+++ b/src/parsing/preparser.h
@@ -926,6 +926,14 @@ class PreParserTraits {
   void SetFunctionNameFromPropertyName(PreParserExpression,
                                        PreParserIdentifier) {}
 
+  inline PreParserExpression RewriteExpression(PreParserExpression expr) {
+    return expr;
+  }
+  inline PreParserExpression RewriteObjectLiteralProperty(
+      PreParserExpression property) {
+    return property;
+  }
+
  private:
   PreParser* pre_parser_;
 };