Remove deprecated StringBuffer.add, addAll and addCharCode.

utils/pub/directory_tree.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.
 
 /// A simple library for rendering a list of files as a directory tree.
 library directory_tree;
 
 import '../../pkg/pathos/lib/path.dart' as path;
 import 'log.dart' as log;
 
@@ skipping 57 matching lines @@
 
   // Walk the map recursively and render to a string.
   var buffer = new StringBuffer();
   _draw(buffer, '', false, null, root);
   return buffer.toString();
 }
 
 void _drawLine(StringBuffer buffer, String prefix, bool isLastChild,
                String name) {
   // Print lines.
-  buffer.add(prefix);
+  buffer.write(prefix);
   if (name != null) {
     if (isLastChild) {
-      buffer.add("'-- ");
+      buffer.write("'-- ");
     } else {
-      buffer.add("|-- ");
+      buffer.write("|-- ");
     }
   }
 
   // Print name.
-  buffer.add(name);
-  buffer.add('\n');
+  buffer.writeln(name);
 }
 
 String _getPrefix(bool isRoot, bool isLast) {
   if (isRoot) return "";
   if (isLast) return "    ";
   return "|   ";
 }
 
 void _draw(StringBuffer buffer, String prefix, bool isLast,
                  String name, Map children) {
@@ skipping 14 matching lines @@
     for (var i = 0; i < childNames.length; i++) {
       _drawChild(i == childNames.length - 1, childNames[i]);
     }
   } else {
     // Show the first few.
     _drawChild(false, childNames[0]);
     _drawChild(false, childNames[1]);
     _drawChild(false, childNames[2]);
 
     // Elide the middle ones.
-    buffer.add(prefix);
-    buffer.add(_getPrefix(name == null, isLast));
-    buffer.add('| (${childNames.length - 6} more...)\n');
+    buffer.write(prefix);
+    buffer.write(_getPrefix(name == null, isLast));
+    buffer.writeln('| (${childNames.length - 6} more...)');
 
     // Show the last few.
     _drawChild(false, childNames[childNames.length - 3]);
     _drawChild(false, childNames[childNames.length - 2]);
     _drawChild(true, childNames[childNames.length - 1]);
   }
 }