fixes css tests, now they can also run in browsers too.

utils/css/tokenizer_base.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.
 // Generated by scripts/tokenizer_gen.py.
 
 
 interface TokenSource {
   Token next();
 }
 
@@ skipping 13 matching lines @@
     var newStack = new InterpStack(stack, quote, isMultiline);
     if (stack != null) newStack.previous = stack;
     return newStack;
   }
 }
 
 /**
  * The base class for our tokenizer. The hand coded parts are in this file, with
  * the generated parts in the subclass Tokenizer.
  */
-class CSSTokenizerBase extends TokenizerHelpers implements TokenSource {
+class CSSTokenizerBase implements TokenSource {
   final SourceFile _source;
   final bool _skipWhitespace;
   String _text;
 
   int _index;
   int _startIndex;
 
   /** Keeps track of string interpolation state. */
   InterpStack _interpStack;
 
@@ skipping 106 matching lines @@
 
     if (_skipWhitespace) {
       return next();
     } else {
       return _finishToken(TokenKind.COMMENT);
     }
   }
 
   void eatDigits() {
     while (_index < _text.length) {
-      if (isDigit(_text.charCodeAt(_index))) {
+      if (TokenizerHelpers.isDigit(_text.charCodeAt(_index))) {
         _index++;
       } else {
         return;
       }
     }
   }
 
   static int _hexDigit(int c) {
     if(c >= 48/*0*/ && c <= 57/*9*/) {
       return c - 48;
@@ skipping 36 matching lines @@
 
     return result;
   }
 
   Token finishNumber() {
     eatDigits();
 
     if (_peekChar() == 46/*.*/) {
       // Handle the case of 1.toString().
       _nextChar();
-      if (isDigit(_peekChar())) {
+      if (TokenizerHelpers.isDigit(_peekChar())) {
         eatDigits();
         return finishNumberExtra(TokenKind.DOUBLE);
       } else {
         _index--;
       }
     }
 
     return finishNumberExtra(TokenKind.INTEGER);
   }
 
   Token finishNumberExtra(int kind) {
     if (_maybeEatChar(101/*e*/) || _maybeEatChar(69/*E*/)) {
       kind = TokenKind.DOUBLE;
       _maybeEatChar(45/*-*/);
       _maybeEatChar(43/*+*/);
       eatDigits();
     }
-    if (_peekChar() != 0 && isIdentifierStart(_peekChar())) {
+    if (_peekChar() != 0 && TokenizerHelpers.isIdentifierStart(_peekChar())) {
       _nextChar();
       return _errorToken("illegal character in number");
     }
 
     return _finishToken(kind);
   }
 
   Token _makeStringToken(List<int> buf, bool isPart) {
     final s = new String.fromCharCodes(buf);
     final kind = isPart ? TokenKind.STRING_PART : TokenKind.STRING;
@@ skipping 174 matching lines @@
       return hexValue;
     } else if (hexValue <= 0x10FFFF){
       world.fatal('unicode values greater than 2 bytes not implemented yet');
       return -1;
     } else {
       return -1;
     }
   }
 
   Token finishDot() {
-    if (isDigit(_peekChar())) {
+    if (TokenizerHelpers.isDigit(_peekChar())) {
       eatDigits();
       return finishNumberExtra(TokenKind.DOUBLE);
     } else {
       return _finishToken(TokenKind.DOT);
     }
   }
 
   Token finishIdentifier(int ch) {
     while (_index < _text.length) {
-      if (!isIdentifierPart(_text.charCodeAt(_index++))) {
+      if (!TokenizerHelpers.isIdentifierPart(_text.charCodeAt(_index++))) {
         _index--;
         break;
       }
     }
     int kind = getIdentifierKind();
     if (kind == TokenKind.IDENTIFIER) {
       return _finishToken(TokenKind.IDENTIFIER);
     } else {
       return _finishToken(kind);
     }
   }
 }