Refactor parser Checkpoints.

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 337 matching lines @@
     // 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;
 
-    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;
 
     // 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;
     typedef ObjectLiteral::Property* ObjectLiteralProperty;
     typedef ZoneList<v8::internal::Expression*>* ExpressionList;
     typedef ZoneList<ObjectLiteral::Property*>* PropertyList;
     typedef ZoneList<v8::internal::Statement*>* StatementList;
 
     // For constructing objects returned by the traversing functions.
     typedef AstNodeFactory<AstConstructionVisitor> Factory;
   };
 
+  class Checkpoint;
+
   explicit ParserTraits(Parser* parser) : parser_(parser) {}
 
   // Custom operations executed when FunctionStates are created and destructed.
   template<typename FunctionState>
   static void SetUpFunctionState(FunctionState* function_state, Zone* zone) {
     Isolate* isolate = zone->isolate();
     function_state->saved_ast_node_id_ = isolate->ast_node_id();
     isolate->set_ast_node_id(BailoutId::FirstUsable().ToInt());
   }
 
@@ skipping 502 matching lines @@
  private:
   static const int kLiteralTypeSlot = 0;
   static const int kElementsSlot = 1;
 
   DISALLOW_IMPLICIT_CONSTRUCTORS(CompileTimeValue);
 };
 
 } }  // namespace v8::internal
 
 #endif  // V8_PARSER_H_