Remove deprecated StringBuffer.add, addAll and addCharCode.

Review URL: https://codereview.chromium.org//12473003

git-svn-id: https://dart.googlecode.com/svn/branches/bleeding_edge/dart/pkg/yaml@19690 260f80e4-7a28-3924-810f-c04153c831b5

pkgs/yaml/lib/parser.dart

diff --git a/pkgs/yaml/lib/parser.dart b/pkgs/yaml/lib/parser.dart
index 386bb59..c84f374 100644
--- a/pkgs/yaml/lib/parser.dart
+++ b/pkgs/yaml/lib/parser.dart
@@ -347,13 +347,13 @@
     capturingAs = false;
     if (!truth(res)) return res;
 
-    capturedString.add(transformation(s.substring(captureStart, pos)));
+    capturedString.write(transformation(s.substring(captureStart, pos)));
     captureStart = pos;
     return res;
   }
 
   void flushCapture() {
-    capturedString.add(s.substring(captureStart, pos));
+    capturedString.write(s.substring(captureStart, pos));
     captureStart = pos;
   }