Remove deprecated string features.

utils/template/codegen.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.
 
 class CGBlock {
   int _blockType;             // Code type of this block
   int _indent;                // Number of spaces to prefix for each statement
   bool _inEach;               // This block or any currently active blocks is a
                               // #each.  If so then any element marked with a
                               // var attribute is repeated therefore the var
@@ skipping 739 matching lines @@
     Iterable<Match> matches = identRe.allMatches(expr);
 
     int lastIdx = 0;
     for (Match m in matches) {
       if (m.start > lastIdx) {
         newExpr.add(expr.substring(lastIdx, m.start));
       }
 
       bool identifier = true;
       if (m.start > 0)  {
-        int charCode = expr.charCodeAt(m.start - 1);
+        int charCode = expr.codeUnitAt(m.start - 1);
         // Starts with ' or " then it's not an identifier.
         identifier = charCode != 34 /* " */ && charCode != 39 /* ' */;
       }
 
       String strMatch = expr.substring(m.start, m.end);
       if (identifier) {
         newExpr.add("${prefixPart}.${strMatch}");
       } else {
         // Quoted string don't touch.
         newExpr.add("${strMatch}");
@@ skipping 233 matching lines @@
       for (String name in names) {
         buff.add("    var ${name} = _scopes[\"${name}\"];\n");
       }
       buff.add("\n");
     }
 
     return buff.toString();
   }
 
 }