Remove cancel and make crash exit with code 253.

sdk/lib/_internal/compiler/implementation/string_validator.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.
 
 // Check the validity of string literals.
 
 library stringvalidator;
 
 import "dart:collection";
 
@@ skipping 64 matching lines @@
    * literals (including an initial 'r' for raw strings).
    */
   String copyWithoutQuotes(String string, int initial, int terminal) {
     assert(0 <= initial);
     assert(0 <= terminal);
     assert(initial + terminal <= string.length);
     return string.substring(initial, string.length - terminal);
   }
 
   void stringParseError(String message, Token token, int offset) {
-    listener.cancel("$message @ $offset", token : token);
+    listener.reportFatalError(
+        token, MessageKind.GENERIC, {'text': "$message @ $offset"});
   }
 
   /**
    * Validates the escape sequences and special characters of a string literal.
    * Returns a DartString if valid, and null if not.
    */
   DartString validateString(Token token,
                             int startOffset,
                             String string,
                             StringQuoting quoting) {
@@ skipping 109 matching lines @@
       return null;
     }
     // String literal successfully validated.
     if (quoting.raw || !containsEscape) {
       // A string without escapes could just as well have been raw.
       return new DartString.rawString(string, length);
     }
     return new DartString.escapedString(string, length);
   }
 }