Fix DDC errors on DDC

lib/src/js/printer.dart

 // 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.
 
 part of js_ast;
 
 
 class JavaScriptPrintingOptions {
   final bool shouldCompressOutput;
   final bool minifyLocalVariables;
@@ skipping 1248 matching lines @@
     }
   }
   bool visitCatch(Catch node) => node.body.accept(this);
   bool visitSwitch(Switch node) => false;
   bool visitCase(Case node) => false;
   bool visitDefault(Default node) => false;
   bool visitFunctionDeclaration(FunctionDeclaration node) => false;
   bool visitLabeledStatement(LabeledStatement node)
       => node.body.accept(this);
   bool visitLiteralStatement(LiteralStatement node) => true;
-  bool visitClassDeclaration(ClassDeclaration) => false;
+  bool visitClassDeclaration(ClassDeclaration node) => false;
 
   bool visitExpression(Expression node) => false;
 }
 
 
 abstract class LocalNamer {
   String getName(Identifier node);
   void enterScope(FunctionExpression node);
   void leaveScope();
 }
@@ skipping 157 matching lines @@
     declare(node.name);
     node.function.accept(this);
   }
 
   visitClassExpression(ClassExpression node) {
     declare(node.name);
     if (node.heritage != null) node.heritage.accept(this);
     for (Method element in node.methods) element.accept(this);
   }
 }