Reject non-ASCII identifiers.

dart/lib/compiler/implementation/scanner/token.dart

 // Copyright (c) 2011, 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.
 
 const int EOF_TOKEN = 0;
 
 const int KEYWORD_TOKEN = $k;
 const int IDENTIFIER_TOKEN = $a;
+const int BAD_INPUT_TOKEN = $X;
 const int DOUBLE_TOKEN = $d;
 const int INT_TOKEN = $i;
 const int HEXADECIMAL_TOKEN = $x;
 const int STRING_TOKEN = $SQ;
 
 const int AMPERSAND_TOKEN = $AMPERSAND;
 const int BACKPING_TOKEN = $BACKPING;
 const int BACKSLASH_TOKEN = $BACKSLASH;
 const int BANG_TOKEN = $BANG;
 const int BAR_TOKEN = $BAR;
@@ skipping 433 matching lines @@
 
 const PrecedenceInfo KEYWORD_INFO =
   const PrecedenceInfo(const SourceString('keyword'), 0, KEYWORD_TOKEN);
 
 const PrecedenceInfo EOF_INFO =
   const PrecedenceInfo(const SourceString('EOF'), 0, EOF_TOKEN);
 
 const PrecedenceInfo IDENTIFIER_INFO =
   const PrecedenceInfo(const SourceString('identifier'), 0, IDENTIFIER_TOKEN);
 
+const PrecedenceInfo BAD_INPUT_INFO =
+  const PrecedenceInfo(const SourceString('malformed input'), 0,
+                       BAD_INPUT_TOKEN);
+
 const PrecedenceInfo OPEN_PAREN_INFO =
   const PrecedenceInfo(const SourceString('('), POSTFIX_PRECEDENCE,
                        OPEN_PAREN_TOKEN);
 
 const PrecedenceInfo CLOSE_PAREN_INFO =
   const PrecedenceInfo(const SourceString(')'), 0, CLOSE_PAREN_TOKEN);
 
 const PrecedenceInfo OPEN_CURLY_BRACKET_INFO =
   const PrecedenceInfo(const SourceString('{'), 0, OPEN_CURLY_BRACKET_TOKEN);
 
@@ skipping 26 matching lines @@
 
 const PrecedenceInfo HEXADECIMAL_INFO =
   const PrecedenceInfo(const SourceString('hexadecimal'), 0, HEXADECIMAL_TOKEN);
 
 const PrecedenceInfo COMMENT_INFO =
   const PrecedenceInfo(const SourceString('comment'), 0, COMMENT_TOKEN);
 
 // For reporting lexical errors.
 const PrecedenceInfo ERROR_INFO =
   const PrecedenceInfo(const SourceString('?'), 0, UNKNOWN_TOKEN);