Remove deprecated StringBuffer.add, addAll and addCharCode.

sdk/lib/json/json_base.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.
 
 // JSON parsing and serialization.
 
 /**
  * Error thrown by JSON serialization if an object cannot be serialized.
  *
  * The [unsupportedObject] field holds that object that failed to be serialized.
@@ skipping 690 matching lines @@
         }
       } else if (charCode == JsonParser.QUOTE ||
           charCode == JsonParser.BACKSLASH) {
         needsEscape = true;
         charCodes.add(JsonParser.BACKSLASH);
         charCodes.add(charCode);
       } else {
         charCodes.add(charCode);
       }
     }
-    sb.add(needsEscape ? new String.fromCharCodes(charCodes) : s);
+    sb.write(needsEscape ? new String.fromCharCodes(charCodes) : s);
   }
 
   void checkCycle(final object) {
     // TODO: use Iterables.
     for (int i = 0; i < seen.length; i++) {
       if (identical(seen[i], object)) {
         throw 'Cyclic structure';
       }
     }
     seen.add(object);
@@ skipping 19 matching lines @@
 
   /**
    * Serializes a [num], [String], [bool], [Null], [List] or [Map] value.
    *
    * Returns true if the value is one of these types, and false if not.
    * If a value is both a [List] and a [Map], it's serialized as a [List].
    */
   bool stringifyJsonValue(final object) {
     if (object is num) {
       // TODO: use writeOn.
-      sb.add(numberToString(object));
+      sb.write(numberToString(object));
       return true;
     } else if (identical(object, true)) {
-      sb.add('true');
+      sb.write('true');
       return true;
     } else if (identical(object, false)) {
-      sb.add('false');
+      sb.write('false');
        return true;
     } else if (object == null) {
-      sb.add('null');
+      sb.write('null');
       return true;
     } else if (object is String) {
-      sb.add('"');
+      sb.write('"');
       escape(sb, object);
-      sb.add('"');
+      sb.write('"');
       return true;
     } else if (object is List) {
       checkCycle(object);
       List a = object;
-      sb.add('[');
+      sb.write('[');
       if (a.length > 0) {
         stringifyValue(a[0]);
         // TODO: switch to Iterables.
         for (int i = 1; i < a.length; i++) {
-          sb.add(',');
+          sb.write(',');
           stringifyValue(a[i]);
         }
       }
-      sb.add(']');
+      sb.write(']');
       seen.removeLast();
       return true;
     } else if (object is Map) {
       checkCycle(object);
       Map<String, Object> m = object;
-      sb.add('{');
+      sb.write('{');
       bool first = true;
       m.forEach((String key, Object value) {
         if (!first) {
-          sb.add(',"');
+          sb.write(',"');
         } else {
-          sb.add('"');
+          sb.write('"');
         }
         escape(sb, key);
-        sb.add('":');
+        sb.write('":');
         stringifyValue(value);
         first = false;
       });
-      sb.add('}');
+      sb.write('}');
       seen.removeLast();
       return true;
     } else {
       return false;
     }
   }
 }