Remove deprecated string features.

sdk/lib/_internal/compiler/implementation/js_backend/minify_namer.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.
 
 part of js_backend;
 
 /**
  * Assigns JavaScript identifiers to Dart variables, class-names and members.
  */
 class MinifyNamer extends Namer {
@@ skipping 76 matching lines @@
 
     // This list of popular instance variable names generated with:
     // cat out.js |
     // perl -ne '$_=~s/(?<![^a-z0-9_\$]\$)\.([a-z0-9_\$]+)/print("$1\n")/gei' |
     // sort | uniq -c | sort -nr | head -40
     // Removed: html, call*, hasOwnProperty.
     _populateSuggestedNames(
         suggestedInstanceNames,
         usedInstanceNames,
         const <String>[
-            r'$add', r'add$1', r'box_0', r'charCodeAt$1', r'constructor',
+            r'$add', r'add$1', r'box_0', r'codeUnitAt$1', r'constructor',
             r'current', r'$defineNativeClass', r'$eq', r'$ne',
             r'getPrototypeOf', r'hasOwnProperty', r'$index', r'$indexSet',
             r'$isJavaScriptIndexingBehavior', r'$isolateProperties',
             r'iterator', r'length', r'$lt', r'$gt', r'$le', r'$ge',
             r'moveNext$0', r'node', r'on', r'prototype', r'push', r'self',
             r'start', r'target', r'this_0', r'value', r'width', r'style']);
 
     _populateSuggestedNames(
         suggestedGlobalNames,
         usedGlobalNames,
@@ skipping 104 matching lines @@
   }
 
   int _alphaNumericNumber(int x) {
     if (x >= ALPHANUMERIC_CHARACTERS) x %= ALPHANUMERIC_CHARACTERS;
     if (x < 26) return $a + x;
     if (x < 52) return $A + x - 26;
     return $0 + x - 52;
   }
 
 }