Check for compile-time constants in DartCompiler

compiler/java/com/google/dart/compiler/ast/DartNodeTraverser.java

 // Copyright (c) 2011, 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.
 
 package com.google.dart.compiler.ast;
 
 import java.util.List;
 
 /**
  * An alternative visitor implementation to {@link DartVisitor}.
@@ skipping 13 matching lines @@
  * }
  * </pre>
  *
  * <p>With DartNodeTraverser, the pre- and post-actions are combined
  * in the same method:
  *
  * <pre>
  * @Override
  * public R visitArrayAccess(DartArrayAccess node) {
  *   // Actions before visiting subnodes.
- *   this.visitChildren(node);
+ *   node.visitChildren(this);
  *   // Actions after visiting subnodes.
+ *   return node;
  * }
  * </pre>
  *
  * <p>In addition, this visitor takes advantage of the AST-node class
  * hierarchy and makes it easy to perform an action for, for example,
  * all statements:
  *
  * <pre>
  * @Override
  * public R visitStatement(DartStatement node) {
@@ skipping 386 matching lines @@
   @Override
   public R visitNativeBlock(DartNativeBlock node) {
     return visitBlock(node);
   }
 
   @Override
   public R visitRedirectConstructorInvocation(DartRedirectConstructorInvocation node) {
     return visitInvocation(node);
   }
 }