[polymer] fix editor hints -- query/queryAll and unused imports

pkg/polymer/lib/deploy.dart

 // Copyright (c) 2013, 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.
 
 /**
  * **Note**: If you already have a `build.dart` in your application, we
  * recommend to use the `package:polymer/builder.dart` library instead.
 
  * Temporary deploy command used to create a version of the app that can be
  * compiled with dart2js and deployed. Following pub layout conventions, this
  * script will treat any HTML file under a package 'web/' and 'test/'
  * directories as entry points.
  *
  * From an application package you can run deploy by creating a small program
  * as follows:
  *
  *    import "package:polymer/deploy.dart" as deploy;
  *    main() => deploy.main();
  *
  * This library should go away once `pub deploy` can be configured to run
  * barback transformers.
  */
 library polymer.deploy;
 
-import 'dart:async';
 import 'dart:io';
 
 import 'package:args/args.dart';
 import 'package:path/path.dart' as path;
 import 'src/build/common.dart' show TransformOptions, phasesForPolymer;
 import 'src/build/runner.dart';
 import 'transformer.dart';
 
 main(List<String> arguments) {
   var args = _parseArgs(arguments);
@@ skipping 102 matching lines @@
     _showUsage(parser);
     return null;
   }
 }
 
 _showUsage(parser) {
   print('Usage: dart --package-root=packages/ '
       'package:polymer/deploy.dart [options]');
   print(parser.getUsage());
 }