Fix deprecated StringBuffer usages 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 226 matching lines @@
    * For this reason, if html snippet start with with tag, this tag must enclose
    * the whole piece. If the tag already has a direction specified, this new one
    * will override existing one in behavior (tested on FF and IE).
    */
   static String _enforceInHtmlHelper(String html, String direction) {
     if (html.startsWith('<')) {
       StringBuffer buffer = new StringBuffer();
       var startIndex = 0;
       Match match = new RegExp('<\\w+').firstMatch(html);
       if (match != null) {
-        buffer..add(html.substring(startIndex, match.end))
-              ..add(' dir=$direction');
+        buffer..write(html.substring(startIndex, match.end))
+              ..write(' dir=$direction');
         startIndex = match.end;
       }
-      return (buffer..add(html.substring(startIndex))).toString();
+      return (buffer..write(html.substring(startIndex))).toString();
     }
     // '\n' is important for FF so that it won't incorrectly merge span groups.
     return '\n<span dir=$direction>$html</span>';
   }
 
   /**
    * Apply bracket guard to [str] using html span tag. This is to address the
    * problem of messy bracket display that frequently happens in RTL layout.
    * If [isRtlContext] is true, then we explicitly want to wrap in a span of RTL
    * directionality, regardless of the estimated directionality.
@@ skipping 29 matching lines @@
    * would return 'firehydrant!'.
    */
   // TODO(efortuna): Get rid of this once this is implemented in Dart.
   // See Issue 2979.
   static String _guardBracketHelper(String str, RegExp regexp, [String before,
       String after]) {
     StringBuffer buffer = new StringBuffer();
     var startIndex = 0;
     Iterable matches = regexp.allMatches(str);
     for (Match match in matches) {
-      buffer..add(str.substring(startIndex, match.start))
-            ..add(before)
-            ..add(str.substring(match.start, match.end))
-            ..add(after);
+      buffer..write(str.substring(startIndex, match.start))
+            ..write(before)
+            ..write(str.substring(match.start, match.end))
+            ..write(after);
       startIndex = match.end;
     }
-    return (buffer..add(str.substring(startIndex))).toString();
+    return (buffer..write(str.substring(startIndex))).toString();
   }
 
   /**
    * Estimates the directionality of [text] using the best known
    * general-purpose method (using relative word counts). A
    * TextDirection.UNKNOWN return value indicates completely neutral input.
    * [isHtml] is true if [text] HTML or HTML-escaped.
    *
    * If the number of RTL words is above a certain percentage of the total
    * number of strongly directional words, returns RTL.
@@ skipping 34 matching lines @@
     }
   }
 
   /**
    * 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));
+      buf.write(str.substring(0, 1));
     }
     // Start at 1 because we're looking for the patterns [\u0591-\u05f2])" or
     // [\u0591-\u05f2]'.
     for (int i = 1; i < str.length; i++) {
       if (str.substring(i, i+1) == '"'
           && new RegExp('[\u0591-\u05f2]').hasMatch(str.substring(i-1, i))) {
-        buf.add('\u05f4');
+        buf.write('\u05f4');
       } else if (str.substring(i, i+1) == "'"
           && new RegExp('[\u0591-\u05f2]').hasMatch(str.substring(i-1, i))) {
-        buf.add('\u05f3');
+        buf.write('\u05f3');
       } else {
-        buf.add(str.substring(i, i+1));
+        buf.write(str.substring(i, i+1));
       }
     }
     return buf.toString();
   }
 
   /**
    * 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;
   }
 }