Rewind additional parser state when reinterpreting arrow arguments

src/parser.h

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef V8_PARSER_H_
 #define V8_PARSER_H_
 
 #include "src/allocation.h"
 #include "src/ast.h"
 #include "src/compiler.h"  // For CachedDataMode
@@ skipping 321 matching lines @@
   bool multiline_;
   bool simple_;
   bool contains_anchor_;
   bool is_scanned_for_captures_;
   bool failed_;
 };
 
 // ----------------------------------------------------------------------------
 // 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;
 
 class ParserTraits {
  public:
   struct Type {
     // TODO(marja): To be removed. The Traits object should contain all the data
     // it needs.
     typedef v8::internal::Parser* Parser;
 
     // Used by FunctionState and BlockState.
     typedef v8::internal::Scope Scope;
     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;
 
     // Return types for traversing functions.
     typedef const AstRawString* Identifier;
     typedef v8::internal::Expression* Expression;
     typedef Yield* YieldExpression;
     typedef v8::internal::FunctionLiteral* FunctionLiteral;
     typedef v8::internal::Literal* Literal;
@@ skipping 516 matching lines @@
  private:
   static const int kLiteralTypeSlot = 0;
   static const int kElementsSlot = 1;
 
   DISALLOW_IMPLICIT_CONSTRUCTORS(CompileTimeValue);
 };
 
 } }  // namespace v8::internal
 
 #endif  // V8_PARSER_H_