Stop using deprecated charCodeAt in Intl

pkg/intl/lib/bidi_utils.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.
 
 part of intl;
 
 /**
  * Bidi stands for Bi-directional text.
  * According to http://en.wikipedia.org/wiki/Bi-directional_text:
  * Bi-directional text is text containing text in both text directionalities,
@@ skipping 335 matching lines @@
     if (total == 0) {
       return hasWeaklyLtr ? TextDirection.LTR : TextDirection.UNKNOWN;
     } else if (rtlCount > _RTL_DETECTION_THRESHOLD * total) {
       return TextDirection.RTL;
     } else {
       return TextDirection.LTR;
     }
   }
 
   /**
-   * Find the first index in [str] of the first closing parenthesis that does
-   * not match an opening parenthesis.
-   */
-  static int _unmatchedParenIndex(String str) {
-    int sum = 0;
-    int index = 0;
-    while (sum >= 0 || index > str.length) {
-      int char = str.charCodeAt(index);
-      if (char == '('.charCodeAt(0))  sum++;
-      else if (char == ')'.charCodeAt(0)) sum--;
-      index++;
-    }
-    return index;
-  }
-
-  /**
    * Replace the double and single quote directly after a Hebrew character in
    * [str] with GERESH and GERSHAYIM. This is most likely the user's intention.
    */
   static String normalizeHebrewQuote(String str) {
     StringBuffer buf = new StringBuffer();
     if (str.length > 0) {
       buf.add(str.substring(0, 1));
     }
     // Start at 1 because we're looking for the patterns [\u0591-\u05f2])" or
     // [\u0591-\u05f2]'.
@@ skipping 13 matching lines @@
 
   /**
    * Check the estimated directionality of [str], return true if the piece of
    * text should be laid out in RTL direction. If [isHtml] is true, the string
    * is HTML or HTML-escaped.
    */
   static bool detectRtlDirectionality(String str, {bool isHtml: false}) {
     return estimateDirectionOfText(str, isHtml: isHtml) == TextDirection.RTL;
   }
 }