fix #155, numeric integer literals

lib/src/js/nodes.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;
 
 abstract class NodeVisitor<T> {
   T visitProgram(Program node);
 
   T visitBlock(Block node);
@@ skipping 1073 matching lines @@
   LiteralString _clone() => new LiteralString(value);
 }
 
 class LiteralNumber extends Literal {
   final String value;  // Must be a valid JavaScript number literal.
 
   LiteralNumber(this.value);
 
   accept(NodeVisitor visitor) => visitor.visitLiteralNumber(this);
   LiteralNumber _clone() => new LiteralNumber(value);
+
+  /**
+   * Use a different precedence level depending on whether the value contains a
+   * dot to ensure we generate `(1).toString()` and `1.0.toString()`.
+   */
+  int get precedenceLevel => value.contains('.') ? PRIMARY : UNARY;
 }
 
 class ArrayInitializer extends Expression {
   final List<Expression> elements;
 
   ArrayInitializer(this.elements);
 
   accept(NodeVisitor visitor) => visitor.visitArrayInitializer(this);
 
   void visitChildren(NodeVisitor visitor) {
@@ skipping 327 matching lines @@
   final Expression expression;
 
   CommentExpression(this.comment, this.expression);
 
   int get precedenceLevel => PRIMARY;
   accept(NodeVisitor visitor) => visitor.visitCommentExpression(this);
   CommentExpression _clone() => new CommentExpression(comment, expression);
 
   void visitChildren(NodeVisitor visitor) => expression.accept(visitor);
 }