Remove deprecated StringBuffer.add, addAll and addCharCode.

sdk/lib/_internal/compiler/implementation/lib/core_patch.dart

Index: sdk/lib/_internal/compiler/implementation/lib/core_patch.dart
diff --git a/sdk/lib/_internal/compiler/implementation/lib/core_patch.dart b/sdk/lib/_internal/compiler/implementation/lib/core_patch.dart
index 1da20f6e90c14bd70e32cbfd216d45c2efffb1d7..350e0fc1f039f55770d82d1510d68ed64724fddf 100644
--- a/sdk/lib/_internal/compiler/implementation/lib/core_patch.dart
+++ b/sdk/lib/_internal/compiler/implementation/lib/core_patch.dart
@@ -248,19 +248,19 @@ patch class NoSuchMethodError {
     if (_arguments != null) {
       for (; i < _arguments.length; i++) {
         if (i > 0) {
-          sb.add(", ");
+          sb.write(", ");
         }
-        sb.add(Error.safeToString(_arguments[i]));
+        sb.write(Error.safeToString(_arguments[i]));
       }
     }
     if (_namedArguments != null) {
       _namedArguments.forEach((String key, var value) {
         if (i > 0) {
-          sb.add(", ");
+          sb.write(", ");
         }
-        sb.add(key);
-        sb.add(": ");
-        sb.add(Error.safeToString(value));
+        sb.write(key);
+        sb.write(": ");
+        sb.write(Error.safeToString(value));
         i++;
       });
     }
@@ -273,9 +273,9 @@ patch class NoSuchMethodError {
       sb = new StringBuffer();
       for (int i = 0; i < _existingArgumentNames.length; i++) {
         if (i > 0) {
-          sb.add(", ");
+          sb.write(", ");
         }
-        sb.add(_existingArgumentNames[i]);
+        sb.write(_existingArgumentNames[i]);
       }
       String formalParameters = sb.toString();
       return "NoSuchMethodError: incorrect number of arguments passed to "