Stop using the Hashable interface.

lib/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("leg.dart");
 #import("scanner/scannerlib.dart");
 #import("tree/tree.dart");
 #import("elements/elements.dart");
 #import("util/characters.dart");
 
-class StringValidator  {
+class StringValidator {
   final DiagnosticListener listener;
 
   StringValidator(this.listener);
 
   DartString validateQuotedString(Token token) {
     SourceString source = token.value;
     StringQuoting quoting = quotingFromString(source);
     int leftQuote = quoting.leftQuoteLength;
     int rightQuote = quoting.rightQuoteLength;
     SourceString content = source.copyWithoutQuotes(leftQuote, rightQuote);
@@ skipping 153 matching lines @@
       }
     }
     // 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);
   }
 }