Revert "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 b04f1dade12b38ea2110a7a28254d8283d34041c..fd24e8d4e952b4d33408f3fc03c0fcb83ec3bf43 100644
--- a/src/parser.h
+++ b/src/parser.h
@@ -339,23 +339,6 @@ class RegExpParser BASE_EMBEDDED {
 // ----------------------------------------------------------------------------
 // JAVASCRIPT PARSING
 
-
-class ParserCheckpoint BASE_EMBEDDED {
- public:
-  template <typename Parser>
-  explicit ParserCheckpoint(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_;
-};
-
-
 class Parser;
 class SingletonLogger;
 
@@ -371,7 +354,6 @@ class ParserTraits {
     typedef v8::internal::Scope* ScopePtr;
     typedef Variable GeneratorVariable;
     typedef v8::internal::Zone Zone;
-    typedef ParserCheckpoint Checkpoint;
 
     typedef v8::internal::AstProperties AstProperties;
     typedef Vector<VariableProxy*> ParameterIdentifierVector;