Remove unused TokenType.IS.

pkg/front_end/test/scanner_test.dart

 // Copyright (c) 2016, 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.
 
 import 'package:front_end/src/base/errors.dart';
 import 'package:front_end/src/base/jenkins_smi_hash.dart';
 import 'package:front_end/src/scanner/errors.dart';
 import 'package:front_end/src/scanner/reader.dart';
 import 'package:front_end/src/scanner/scanner.dart';
 import 'package:front_end/src/scanner/token.dart';
@@ skipping 1340 matching lines @@
     expect(TokenType.CARET.isOperator, isTrue);
     expect(TokenType.CARET_EQ.isOperator, isTrue);
     expect(TokenType.EQ.isOperator, isTrue);
     expect(TokenType.EQ_EQ.isOperator, isTrue);
     expect(TokenType.GT.isOperator, isTrue);
     expect(TokenType.GT_EQ.isOperator, isTrue);
     expect(TokenType.GT_GT.isOperator, isTrue);
     expect(TokenType.GT_GT_EQ.isOperator, isTrue);
     expect(TokenType.INDEX.isOperator, isTrue);
     expect(TokenType.INDEX_EQ.isOperator, isTrue);
-    expect(TokenType.IS.isOperator, isTrue);
     expect(TokenType.LT.isOperator, isTrue);
     expect(TokenType.LT_EQ.isOperator, isTrue);
     expect(TokenType.LT_LT.isOperator, isTrue);
     expect(TokenType.LT_LT_EQ.isOperator, isTrue);
     expect(TokenType.MINUS.isOperator, isTrue);
     expect(TokenType.MINUS_EQ.isOperator, isTrue);
     expect(TokenType.MINUS_MINUS.isOperator, isTrue);
     expect(TokenType.PERCENT.isOperator, isTrue);
     expect(TokenType.PERCENT_EQ.isOperator, isTrue);
     expect(TokenType.PERIOD_PERIOD.isOperator, isTrue);
@@ skipping 39 matching lines @@
   _TestScanner(CharacterReader reader, [this.listener]) : super(reader);
 
   @override
   void reportError(
       ScannerErrorCode errorCode, int offset, List<Object> arguments) {
     if (listener != null) {
       listener.errors.add(new TestError(offset, errorCode, arguments));
     }
   }
 }