Remove more warnings.

lib/compiler/implementation/tree/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.
 
 interface Visitor<R> {
   R visitBlock(Block node);
   R visitBreakStatement(BreakStatement node);
   R visitCascade(Cascade node);
   R visitCascadeReceiver(CascadeReceiver node);
   R visitCaseMatch(CaseMatch node);
@@ skipping 1123 matching lines @@
 
   bool isStatic() => (flags & FLAG_STATIC) != 0;
   bool isAbstract() => (flags & FLAG_ABSTRACT) != 0;
   bool isFinal() => (flags & FLAG_FINAL) != 0;
   bool isVar() => (flags & FLAG_VAR) != 0;
   bool isConst() => (flags & FLAG_CONST) != 0;
   bool isFactory() => (flags & FLAG_FACTORY) != 0;
   bool isExternal() => (flags & FLAG_EXTERNAL) != 0;
 
   /**
-   * Use this to check if the declaration is either explicitly or implicitly 
+   * Use this to check if the declaration is either explicitly or implicitly
    * final.
    */
   bool isFinalOrConst() => isFinal() || isConst();
 
   String toString() {
     LinkBuilder<String> builder = new LinkBuilder<String>();
     if (isStatic()) builder.addLast('static');
     if (isAbstract()) builder.addLast('abstract');
     if (isFinal()) builder.addLast('final');
     if (isVar()) builder.addLast('var');
@@ skipping 408 matching lines @@
 
   final Token beginToken;
   final Token endToken;
 
   ScriptTag(this.tag, this.argument, this.prefixIdentifier, this.prefix,
             this.beginToken, this.endToken);
 
   bool isImport() => tag.source == const SourceString("import");
   bool isSource() => tag.source == const SourceString("source");
   bool isLibrary() => tag.source == const SourceString("library");
-  bool isResource() => tag.source == const SourceString("resource");
 
   ScriptTag asScriptTag() => this;
 
   accept(Visitor visitor) => visitor.visitScriptTag(this);
 
   visitChildren(Visitor visitor) {
     tag.accept(visitor);
     argument.accept(visitor);
     if (prefixIdentifier !== null) prefixIdentifier.accept(visitor);
     if (prefix !== null) prefix.accept(visitor);
@@ skipping 178 matching lines @@
  * argument).
  *
  * TODO(ahe): This method is controversial, the team needs to discuss
  * if top-level methods are acceptable and what naming conventions to
  * use.
  */
 initializerDo(Node node, f(Node node)) {
   SendSet send = node.asSendSet();
   if (send !== null) return f(send.arguments.head);
 }