Implement const expressions for local variables

runtime/vm/ast.h

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #ifndef VM_AST_H_
 #define VM_AST_H_
 
 #include "platform/assert.h"
 #include "vm/allocation.h"
 #include "vm/growable_array.h"
@@ skipping 946 matching lines @@
   const LocalVariable& local() const { return local_; }
   AstNode* pseudo() const { return pseudo_; }  // Can be NULL.
   bool HasPseudo() const { return pseudo_ != NULL; }
 
   virtual void VisitChildren(AstNodeVisitor* visitor) const {
     if (HasPseudo()) {
       pseudo()->Visit(visitor);
     }
   }
 
+  virtual const Instance* EvalConstExpr() const;
   virtual AstNode* MakeAssignmentNode(AstNode* rhs);
 
   DECLARE_COMMON_NODE_FUNCTIONS(LoadLocalNode);
 
  private:
   const LocalVariable& local_;
   AstNode* pseudo_;
 
   DISALLOW_IMPLICIT_CONSTRUCTORS(LoadLocalNode);
 };
@@ skipping 726 matching lines @@
   const LocalVariable& context_var_;
 
   DISALLOW_IMPLICIT_CONSTRUCTORS(InlinedFinallyNode);
 };
 
 }  // namespace dart
 
 #undef DECLARE_COMMON_NODE_FUNCTIONS
 
 #endif  // VM_AST_H_