Remove deprecated StringBuffer.add, addAll and addCharCode.

runtime/lib/errors_patch.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.
 
 patch class Error {
   /* patch */ static String _objectToString(Object object) {
     return Object._toString(object);
   }
 }
 
@@ skipping 89 matching lines @@
     }
     return "$msg\n\n";
   }
 
   /* patch */ String toString() {
     StringBuffer actual_buf = new StringBuffer();
     int i = 0;
     if (_arguments != null) {
       for (; i < _arguments.length; i++) {
         if (i > 0) {
-          actual_buf.add(", ");
+          actual_buf.write(", ");
         }
-        actual_buf.add(Error.safeToString(_arguments[i]));
+        actual_buf.write(Error.safeToString(_arguments[i]));
       }
     }
     if (_namedArguments != null) {
       _namedArguments.forEach((String key, var value) {
         if (i > 0) {
-          actual_buf.add(", ");
+          actual_buf.write(", ");
         }
-        actual_buf.add(key);
-        actual_buf.add(": ");
-        actual_buf.add(Error.safeToString(value));
+        actual_buf.write(key);
+        actual_buf.write(": ");
+        actual_buf.write(Error.safeToString(value));
         i++;
       });
     }
     var args_mismatch = _existingArgumentNames != null;
     StringBuffer msg_buf = new StringBuffer(_developerMessage(args_mismatch));
     if (!args_mismatch) {
-      msg_buf.add(
+      msg_buf.write(
           "NoSuchMethodError : method not found: '$_memberName'\n"
           "Receiver: ${Error.safeToString(_receiver)}\n"
           "Arguments: [$actual_buf]");
     } else {
       String actualParameters = actual_buf.toString();
       StringBuffer formal_buf = new StringBuffer();
       for (int i = 0; i < _existingArgumentNames.length; i++) {
         if (i > 0) {
-          formal_buf.add(", ");
+          formal_buf.write(", ");
         }
-        formal_buf.add(_existingArgumentNames[i]);
+        formal_buf.write(_existingArgumentNames[i]);
       }
       String formalParameters = formal_buf.toString();
-      msg_buf.add( 
+      msg_buf.write(
           "NoSuchMethodError: incorrect number of arguments passed to "
           "method named '$_memberName'\n"
           "Receiver: ${Error.safeToString(_receiver)}\n"
           "Tried calling: $_memberName($actualParameters)\n"
           "Found: $_memberName($formalParameters)");
     }
     return msg_buf.toString();
   }
 }