merge fasta.Token into analyzer.Token

pkg/front_end/lib/src/scanner/errors.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/fasta/fasta_codes.dart';
 import 'package:front_end/src/fasta/scanner/error_token.dart';
-import 'package:front_end/src/fasta/scanner/token.dart';
+import 'package:front_end/src/scanner/token.dart' show Token;
 import 'package:front_end/src/fasta/scanner/token_constants.dart';
 
 /**
  * The error codes used for errors detected by the scanner.
  */
 class ScannerErrorCode extends ErrorCode {
   /**
    * Parameters:
    * 0: the illegal character
    */
@@ skipping 118 matching lines @@
     token = token.next;
     // If we've found an EOF token, its charOffset indicates where the end of
     // the input is.
     if (token.isEof) return token.charOffset == charOffset;
     // If we've found a non-error token, then we know there is additional input
     // text after [charOffset].
     if (token.type.kind != BAD_INPUT_TOKEN) return false;
     // Otherwise keep looking.
   }
 }